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Rifampin

Medically reviewed by Drugs.com. Last updated on Sep 4, 2020.

Pronunciation

(rif AM pin)

Index Terms

  • Rifampicin

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product

Capsule, Oral:

Rifadin: 150 mg [DSC], 300 mg [DSC] [contains brilliant blue fcf (fd&c blue #1), corn starch, fd&c red #40]

Generic: 150 mg, 300 mg

Solution Reconstituted, Intravenous [preservative free]:

Rifadin: 600 mg (1 ea)

Rifadin: 600 mg (1 ea) [contains sodium formaldehyde sulfoxylate]

Generic: 600 mg (1 ea)

Brand Names: U.S.

  • Rifadin

Pharmacologic Category

  • Antitubercular Agent
  • Rifamycin

Pharmacology

Inhibits bacterial RNA synthesis by binding to the beta subunit of DNA-dependent RNA polymerase, blocking RNA transcription

Absorption

Oral: Well absorbed; food may delay or slightly reduce peak

Distribution

Crosses the blood-brain barrier well

Relative diffusion of antimicrobial agents from blood into cerebrospinal fluid (CSF): Adequate with or without inflammation (exceeds usual MICs)

Ratio of CSF to blood level (%): Inflamed meninges: 25

Metabolism

Hepatic; undergoes enterohepatic recirculation

Excretion

Feces (60% to 65%) and urine (~30%) as unchanged drug

Time to Peak

Serum: Oral: 2 to 4 hours

Duration of Action

≤24 hours

Half-Life Elimination

3 to 4 hours, prolonged with hepatic impairment; End-stage renal disease: 1.8 to 11 hours

Protein Binding

80%

Special Populations: Children

After oral administration, the Cmax ranged from 3.5 to 15 mcg/mL, Tmax was 1 hour, and half-life was approximately 2.9 hours. After IV administration, the Cmax after the initial infusion was approximately 25.9 mcg/mL and half-life ranged from 1.04 to 3.81 hours.

Use: Labeled Indications

Meningococcal prophylaxis: Treatment of asymptomatic carriers of Neisseria meningitidis to eliminate meningococci from the nasopharynx.

Tuberculosis: Treatment of tuberculosis in combination with other agents.

Off Label Uses

Anaplasmosis, symptomatic

Based on the Infectious Diseases Society of America (IDSA) guidelines for the clinical assessment, treatment, and prevention of Lyme disease, human granulocytic anaplasmosis (HGA), and babesiosis and the Centers for Disease Control and Prevention (CDC) guideline for the diagnosis and management of tickborne rickettsial diseases: Rocky Mountain spotted fever (RMSF) and other spotted fever group rickettsioses, ehrlichioses, and anaplasmosis, rifampin may be considered as an alternative therapy to doxycycline for the treatment of mild cases of HGA in patients who are pregnant or who have a severe drug allergy to doxycycline. Due to similar symptoms, RMSF should be ruled out before considering rifampin treatment for human anaplasmosis; rifampin is not an acceptable treatment of RMSF. In addition, rifampin does not treat coinfection with Lyme disease (Borrelia burgdorferi) [CDC [Biggs 2016]], [IDSA [Wormser 2006]].

Bartonella spp. infections

Based on the US Department of Health and Human Services guidelines for prevention and treatment of opportunistic infections in adults and adolescents with HIV, rifampin is a recommended and effective adjunctive agent for treatment of bacteremia with or without endocarditis and other severe infections (including CNS) due to Bartonella in adolescent and adult patients with HIV [HHS [OI adult] 2020].

Clinical experience also suggests the utility of rifampin in managing lymphadenitis and disseminated disease due to Bartonella in patients without HIV[Rolain 2004], [Spach 2020c].

Brucellosis

Data from randomized studies support the use of rifampin, in combination with doxycycline, as an alternative regimen for the treatment of brucellosis [Hashemi 2012], [Solera 1995].

Based on the World Health Organization (WHO) and the CDC guidelines for brucellosis, rifampin, in combination with doxycycline, is effective and recommended in the management of uncomplicated brucellosis [CDC 2017], [WHO [Corbel 2006]].

Cholestatic pruritus

Data from a meta-analysis of randomized controlled trials support the use of rifampin in the treatment of cholestatic pruritus [Khurana 2006].

American Association for the Study of Liver Diseases practice guidelines for primary biliary cholangitis recommend the use of rifampin for cholestatic pruritus refractory to bile acid sequestrants [AASLD [Lindor 2019]].

Endocarditis, treatment

Based on the American Heart Association scientific statement on infective endocarditis in adults, rifampin (in combination with other antibiotics) is an effective and recommended treatment regimen for infective endocarditis due to staphylococci (methicillin-susceptible or methicillin-resistant) involving a prosthetic valve [AHA [Baddour 2015]].

Hidradenitis suppurativa, moderate to severe

Data from a limited number of patients in a small number of studies suggest rifampin in combination with clindamycin may be beneficial in the management of hidradenitis suppurativa [Dessinioti 2016], [Gener 2009], [van der Zee 2009].

Based on North American clinical management guidelines for hidradenitis suppurativa from the United States and Canadian Hidradenitis Suppurativa Foundations, rifampin in combination with clindamycin is an effective and recommended treatment regimen for this condition [Alikhan 2019].

Leprosy

Based on the National Hansen's Disease Program treatment recommendations and WHO guidelines for the diagnosis, treatment, and prevention of leprosy, rifampin, in combination with other agents, is an effective and recommended treatment for lepromatous (multibacillary) and tuberculoid (paucibacillary) leprosy.

Meningococcal disease, chemoprophylaxis after close contact with a patient with invasive disease

Based on the Advisory Committee on Immunization Practices recommendations for prevention and control of Haemophilus influenzae type b (Hib) disease, rifampin is effective and recommended as chemoprophylaxis in index patients with invasive Hib disease (unless treated with cefotaxime or ceftriaxone); all household contacts in households with members <4 years of age who are not fully vaccinated or members <18 years of age who are immunocompromised, regardless of their vaccination status; and childcare settings when 2 or more cases of invasive Hib disease have occurred within 60 days and unimmunized or under-immunized children attend the facility [ACIP [Briere 2014]].

Mycobacterial (nontuberculous) infection

Based on the American Thoracic Society and IDSA guideline for the diagnosis, treatment, and prevention of nontuberculous mycobacterial diseases, the British Thoracic Society guidelines for the management of nontuberculous mycobacterial pulmonary disease, and the US Cystic Fibrosis Foundation and European Cystic Fibrosis Society consensus recommendations for the management of nontuberculous mycobacteria in individuals with cystic fibrosis, rifampin (in combination with other antimicrobials) is effective and recommended for the treatment of Mycobacterium avium complex infection [ATS/IDSA [Griffith 2007]], [BTS [Haworth 2017]], [CFF/ECFS [Floto 2016]].

Staphylococcus spp. infections, including bone and joint and CNS

Based on IDSA guidelines for the treatment of methicillin-resistant Staphylococcus aureus infections, the diagnosis and management of prosthetic joint infection, the management of bacterial meningitis, and the management of health care–associated ventriculitis and meningitis, rifampin is an effective and recommended adjunctive agent for the treatment of device- or hardware-related infections caused by Staphylococcus spp. The use of rifampin warrants increased awareness of possible drug interactions caused by liver enzyme induction. Rifampin should only be used in combination with other antibiotics for S. aureus infections because resistance can develop rapidly with monotherapy [IDSA [Liu 2011]], [IDSA [Osmon 2013]], [IDSA [Tunkel 2004]], [IDSA [Tunkel 2017].

Streptococcus (group A) chronic carriage

Based on the IDSA clinical practice guideline for the diagnosis and management of group A streptococcal pharyngitis, rifampin (in combination with oral penicillin V or intramuscular benzathine penicillin G) is an effective and recommended treatment option in chronic carriers of group A Streptococcus [IDSA [Shulman 2012]].

Contraindications

Hypersensitivity to rifampin, any rifamycins, or any component of the formulation; concurrent use of atazanavir, darunavir, fosamprenavir, praziquantel, ritonavir/saquinavir, saquinavir, or tipranavir.

Canadian labeling: Additional contraindications (not in US labeling): Jaundice associated with reduced bilirubin excretion; premature and newborn infants; breastfeeding women; hepatic function impairment.

Dosing: Adult

Anaplasmosis, symptomatic (alternative agent) (off-label use):

Note: Reserve use for patients with severe allergy or intolerance to doxycycline. Rifampin is not effective for Rocky Mountain spotted fever or Lyme disease. If concurrent Lyme disease is suspected, use as part of an appropriate combination regimen (CDC [Biggs 2016]; IDSA [Wormser 2006]).

Oral: 300 mg twice daily for 7 to 10 days (CDC [Biggs 2016]; IDSA [Wormser 2006]).

Bartonella spp. infections (off-label use):

Bacteremia with or without endocarditis (alternative adjunctive agent when gentamicin cannot be used): Oral, IV: 300 mg twice daily in combination with doxycycline for 14 days, followed by doxycycline monotherapy (Rolain 2004; Spach 2020a; Spach 2020b). Some experts do not suggest rifampin as part of the regimen for patients with HIV and bacteremia without endocarditis (HHS [OI adult] 2020).

Other severe infection (including CNS infection) in patients with HIV: Oral, IV: 300 mg twice daily as part of an appropriate combination regimen. Duration of therapy is at least 3 months and depends on clinical course (HHS [OI adult] 2020). Note: For CNS infection, use of adjunctive rifampin is optional (HHS [OI adult] 2020).

Cat scratch disease, lymphadenitis (alternative agent): Oral: 300 mg twice daily for 7 to 10 days (Spach 2020c).

Cat scratch disease, disseminated in patients without HIV (hepatosplenic, prolonged systemic febrile illness, CNS infection, neuroretinitis): Oral, IV: 300 mg twice daily as part of an appropriate combination regimen. Duration is 10 to 14 days for hepatosplenic disease or prolonged systemic febrile illness and 4 to 6 weeks for CNS infection or neuroretinitis (Rolain 2004; Spach 2020c).

Brucellosis (off-label use):

Treatment: Oral: 600 to 900 mg once daily as part of an appropriate combination regimen. Duration is 6 weeks for uncomplicated nonfocal infection and at least 12 weeks for spondylitis, neurobrucellosis, and endocarditis (Alp 2008; Ariza 2007; Bosilkovski 2020; CDC 2017; Jia 2017; Skalsky 2008; Solera 1999; WHO [Corbel 2006]; Zheng 2018).

Postexposure prophylaxis (high-risk laboratory exposure): Note: For exposure to Brucella abortus RB51, use an alternative prophylactic regimen due to resistance.

Oral: 600 mg once daily in combination with doxycycline for 3 weeks (Bosilkovski 2020; CDC 2017).

Cholestatic pruritus (alternative agent) (off-label use):

Note: Avoid use in patients with a baseline bilirubin >2.5 mg/dL (AASLD [Lindor 2019]).

Oral: 150 to 300 mg twice daily (Poupon 2020).

Endocarditis, treatment (off-label use):

Staphylococcus spp. or early (<1 year) culture negative (prosthetic valve): Oral, IV: 900 mg/day in 3 equally divided doses as part of an appropriate combination regimen for ≥6 weeks; delay initiation of rifampin until 3 to 5 days after initiation of the other agents (AHA [Baddour 2015]; IDSA [Liu 2011]; Karchmer 2020).

Hidradenitis suppurativa, moderate to severe (alternative agent) (off-label use):

Oral: 600 mg/day in 1 or 2 divided doses in combination with clindamycin for 10 to 12 weeks (Alikhan 2019; Dessinioti 2016; Gener 2009; Gulliver 2016; van der Zee 2009).

Leprosy (off-label use):

Oral: 600 mg once daily as part of an appropriate combination regimen for 12 months for tuberculoid (paucibacillary) disease and 24 months for lepromatous (multibacillary) disease (NHDP/HRSA 2018). Note: Rifampin is given once monthly if coadministered with prednisone (NHDP/HRSA 2018). For resource-limited settings, the World Health Organization recommends 600 mg once monthly as part of an appropriate combination regimen for 6 months (paucibacillary) or 12 months (multibacillary) (WHO 2018).

Meningococcal disease, chemoprophylaxis after close contact with a patient with invasive disease:

Oral: 600 mg twice daily for 2 days. Note: Administer prophylaxis as soon as possible following exposure (ideally <24 hours after identification of index patient). Close contacts include persons with prolonged exposure (≥8 hours) in close proximity (<3 feet) to index patient or direct exposure to oral secretions (eg, household contacts, childcare center contacts) (AAP [Red Book 2015]; ACIP [Bilukha 2005]; ACIP [Cohn 2013]; Gardner 2006).

Mycobacterial (nontuberculous) infection (off-label use):

Mycobacterium avium complex infection:

Pulmonary disease, nonsevere noncavitary nodular/bronchiectatic disease in patients without cystic fibrosis: Oral: 600 mg 3 times weekly as part of an appropriate combination regimen (ATS/IDSA [Griffith 2007]; BTS [Haworth 2017]).

Pulmonary disease, severe nodular/bronchiectatic disease, cavitary disease, or disease in patients with cystic fibrosis: Oral: 600 mg once daily as part of an appropriate combination regimen; reduce dose to 450 mg once daily for patients weighing <50 kg (ATS/IDSA [Griffith 2007]; CFF/ECFS [Floto 2016]).

Duration of therapy: Continue treatment until patient is culture negative on therapy for ≥1 year (ATS/IDSA [Griffith 2007]; BTS [Haworth 2017]; CFF/ECFS [Floto 2016]).

Staphylococcus spp. infections, including bone and joint and CNS (adjunctive agent) (off-label use):

Note: Used primarily in the setting of retained hardware or other prosthetic material for activity against biofilm formation (IDSA [Liu 2011]; Zimmerli 1998; Zimmerli 2019).

Oral, IV: 600 mg once daily or 300 to 450 mg twice daily in combination with an appropriate antistaphylococcal agent(s). Duration varies based on patient-specific factors, infection site, and intervention (Baddour 2020; IDSA [Liu 2011]). Some experts suggest delaying initiation of rifampin until several days after initiation of other antistaphylococcal agents (Berbari 2020; Osmon 2020).

Streptococcus (group A) chronic carriage (off-label use):

Note: Most individuals with chronic carriage do not require antibiotics (IDSA [Shulman 2012]).

Oral: 600 mg/day in 1 or 2 divided doses for the last 4 days of treatment in combination with penicillin V (Chaudhary 1985; IDSA [Shulman 2012]) or for 4 days in combination with single-dose IM benzathine penicillin G (IDSA [Shulman 2012]; Tanz 1985).

Tuberculosis, active (drug susceptible):

Note: Always administer in combination with other antitubercular drugs (ATS/CDC/IDSA [Nahid 2016]).

Oral, IV:

Initial intensive phase: 10 mg/kg (maximum dose: 600 mg) once daily (or 5 days per week by directly observed therapy [DOT]) as part of a standard 4-drug regimen for 2 months (ATS/CDC/IDSA [Nahid 2016]).

Continuation phase: 10 mg/kg (maximum dose: 600 mg) once daily (or 5 days per week by DOT) in combination with isoniazid for at least 4 months or longer for cavitary disease with positive cultures (7 months), bone and joint disease (6 to 9 months), and CNS disease (≥12 months) (ATS/CDC/IDSA [Nahid 2016]).

Alternative dosing intervals: Daily or 5-times-weekly dosing is preferred, particularly during the intensive phase. If neither is feasible, alternatives in order of preference are: daily (or 5-times-weekly) dosing for the intensive phase followed by 3-times-weekly dosing during the continuation phase; 3-times-weekly dosing for the duration of treatment; and daily dosing for 2 weeks followed by twice-weekly dosing. Use DOT for <7 days/week dosing (ATS/CDC/IDSA [Nahid 2016]).

Tuberculosis, latent infection:

Oral: 10 mg/kg (maximum dose: 600 mg) once daily as a single agent for 4 months or in combination with isoniazid for 3 months (CDC [Sterling 2020]).

Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.

Dosing: Geriatric

Refer to adult dosing.

Dosing: Pediatric

Note: Rifampin monotherapy is rarely indicated; most indications require combination therapy with other antimicrobial agent. Recommendations often change due to epidemiology (resistance) and emerging information; consult CDC and WHO for current recommendations, as appropriate (ATS/CDC/IDSA [Nahid 2016]; WHO 2010; WHO 2014).

Active tuberculosis infection (excluding meningitis), treatment (drug susceptible): Note: Always use as part of a multidrug regimen. Any regimens using less than once daily dosing should administer dosing as directly observed therapy (DOT). Treatment regimens for pulmonary tuberculosis consist of an initial 2-month intensive phase of a 4-drug regimen, followed by a continuation phase of an additional 4 to 7 months of isoniazid and rifampin. Rifampin frequency and dosing differs depending on treatment regimen selected; consult current drug-sensitive TB guidelines for detailed information (ATS/CDC/IDSA [Nahid 2016].

ATS/CDC/IDSA Recommendations (ATS/CDC/IDSA [Nahid 2016]): Note: For HIV-exposed/-positive, refer to specific guidelines for guidance on drug interaction management with antiretroviral therapy (see Drug-Drug Interactions)

Once daily or 5-times-weekly (DOT):

Infants, Children, and Adolescents <15 years, weighing ≤40 kg: Oral, IV: 10 to 20 mg/kg/dose once daily; maximum dose: 600 mg/dose

Children and Adolescents <15 years weighing >40 kg or Adolescents ≥15 years: Oral, IV: 10 mg/kg/dose once daily (typical dose: 600 mg)

Three-times-weekly DOT: Note: Although suggested dosing based on experience with twice-weekly regimen; experts suggest three-times-weekly regimens are more effective than twice-weekly DOT regimens; three-times-weekly DOT may be used as part of an intensive phase and/or continuation phase dosing regimen; consult guidelines for specific information

Infants, Children, and Adolescents <15 years, weighing ≤40 kg: Oral, IV: 10 to 20 mg/kg/dose 3-times-weekly; maximum dose: 600 mg/dose

Children and Adolescents <15 years weighing >40 kg or Adolescents ≥15 years: Oral, IV: 10 mg/kg/dose 3-times-weekly (typical dose: 600 mg)

Twice-weekly DOT: Note: Regimen not generally recommended; do not use in HIV patients or those with smear-positive and/or cavitary disease. This therapy should only be used following completion of a 2-week intensive phase once-daily (or 5-times-weekly) regimen. Missed doses result in the equivalent of once-weekly dosing which has been shown to be inferior and is associated with treatment failure, relapse, and development of drug resistance.

Infants, Children, and Adolescents <15 years, weighing ≤40 kg: Oral, IV: 10 to 20 mg/kg/dose twice weekly; maximum dose: 600 mg/dose

Children and Adolescents <15 years weighing >40 kg or Adolescents ≥15 years: Oral, IV: 10 mg/kg/dose twice weekly (typical dose: 600 mg)

Latent tuberculosis infection (LTBI), treatment: Note: May be considered for those unable to tolerate isoniazid or if isoniazid-resistance is suspected.

Non-HIV-exposed/-positive:

Infants, Children, and Adolescents: Oral: 15 to 20 mg/kg/dose once daily; maximum dose: 600 mg/dose; use in combination with isoniazid for 3 to 4 months or as monotherapy for 4 months (CDC 2018; Diallo 2018; Red Book [AAP 2018]; WHO 2018). Note: Lower doses of 10 mg/kg/day have been described; however, pharmacokinetic studies suggest that lower doses of rifampin do not provide adequate drug exposure (Kwara 2016). In addition, one clinical trial comparing 4 months of rifampin monotherapy to 9 months of isoniazid monotherapy in pediatric patients (n=422 in the rifampin group; age range: 0 to 17 years; rifampin dose: 15 to 20 mg/kg/dose) showed similar rates of efficacy and better treatment adherence (Diallo 2018).

HIV-exposed/-positive: Note: Not appropriate for all HIV patients due to drug-drug interactions with some antiretrovirals; refer to specific guidelines for guidance on drug interaction management with antiretroviral therapy (see Drug-Drug Interactions)

Infants and Children: Oral: 10 to 20 mg/kg/dose once daily; maximum dose: 600 mg/dose; use in combination with isoniazid for 3 to 4 months or as monotherapy for 4 to 6 months (HHS [OI pediatric 2018]); continue therapy for 6 months if exposure to an isoniazid mono-resistant source case (HHS [OI pediatric 2018]; WHO 2018). Note: Pharmacokinetic studies suggest that lower doses of rifampin do not provide adequate drug exposure (Kwara 2016).

Adolescents: Oral: 600 mg once daily for 4 months (HHS [OI adult 2018])

Catheter (peritoneal dialysis); exit-site or tunnel infection: Infants, Children, and Adolescents: Oral: 10 to 20 mg/kg/day divided into 2 doses. Maximum dose: 600 mg/dose (ISPD [Warady 2012]). Note: Should not be used as monotherapy or routinely used in areas where TB is endemic.

Endocarditis:

Empiric therapy, prosthetic valve/material (AHA [Baltimore 2015]): Note: Use in combination with other antibiotics:

Early infection (≤1 year postop)/nosocomial infection associated with cannulation: Children and Adolescents: Oral, IV: 20 mg/kg/day divided every 8 hours; maximum daily dose: 900 mg/day

Late infection (>1 year postop): Children and Adolescents: Oral, IV: 15 to 20 mg/kg/day divided every 12 hours; maximum daily dose: 600 mg/day

MRSA infection, prosthetic valve: Infants, Children, and Adolescents: Oral, IV: 15 mg/kg/day divided every 8 hours; maximum daily dose: 900 mg/day (IDSA [Liu 2011])

H. influenzae prophylaxis: Infants, Children, and Adolescents: Oral: 20 mg/kg/day once daily for 4 days, not to exceed 600 mg/dose (Kliegman 2016; Red Book [AAP 2018])

Meningococcal prophylaxis: Infants, Children, and Adolescents: Oral: 20 mg/kg/day in divided doses every 12 hours for 2 days, not to exceed 600 mg/dose

Peritonitis (peritoneal dialysis), treatment: Infants, Children, and Adolescents: Oral: 10 to 20 mg/kg/day divided into 2 doses; maximum dose: 600 mg/dose (ISPD [Warady 2012])

Pharyngeal chronic carriers of group A streptococci, treatment: Children and Adolescents: Oral: 20 mg/kg/day once daily for the last 4 days of treatment when combined with oral penicillin V or 20 mg/kg/day in 2 divided doses for 4 days when combined with intramuscular benzathine penicillin G; maximum daily dose: 600 mg/day (IDSA [Shulman 2012])

Staphylococcus aureus, nasal carriers: Children and Adolescents: Oral, IV: 15 mg/kg/day divided every 12 hours for 5 to 10 days; Note: Must use in combination with at least one other systemic antistaphylococcal antibiotic. Maximum daily dose: 600 mg/day. Not recommended as first-line drug for decolonization; evidence is weak for use in patients with recurrent infections (IDSA [Liu 2011]).

Dosage adjustment for concomitant therapy: Significant drug interactions exist, requiring dose/frequency adjustment or avoidance. Consult drug interactions database for more information.

Reconstitution

Reconstitute vial with 10 mL SWFI. Prior to injection, dilute in appropriate volume of a compatible solution (eg, 100 mL D5W).

Extemporaneously Prepared

25 mg/mL Oral Suspension (ASHP Standard Concentration) (ASHP 2017)

A 25 mg/mL oral suspension may be made with capsules and one of three different vehicles (a 1:1 mixture of Ora-Sweet and Ora-Plus, a 1:1 mixture of Ora-Sweet SF and Ora-Plus, or cherry syrup concentrate diluted 1:4 with simple syrup, NF). Empty the contents of ten 300 mg capsules into a mortar and reduce to a fine powder. Add 20 mL of the vehicle and mix to a uniform paste; mix while adding the vehicle in incremental proportions to almost 120 mL; transfer to a calibrated bottle, rinse mortar with vehicle, and add quantity of vehicle sufficient to make 120 mL. Label "shake well," “protect from light” and " refrigerate." Stable for 28 days refrigerated (preferred) or at room temperature (Allen 1998; Nahata 2014).

Allen LV Jr, Erickson MA. Stability of bethanechol chloride, pyrazinamide, quinidine sulfate, rifampin, and tetracycline hydrochloride in extemporaneously compounded oral liquids. Am J Health Syst Pharm. 1998;55(17):1804-1809.9775343Nahata MC and Pai VB. Pediatric Drug Formulations. 6th ed. Cincinnati, OH: Harvey Whitney Books Co; 2014.

10 mg/mL Oral Suspension

A 10 mg/mL oral suspension may be made with capsules and simple syrup, NF. Empty the contents of four 300 mg capsules into a mortar. If necessary, crush contents to produce a fine powder. Add 20 mL of simple syrup, NF and mix to a uniform paste; mix while adding simple syrup in incremental proportions to almost 120 mL; transfer to a calibrated bottle, rinse mortar with simple syrup, and add quantity of vehicle sufficient to make 120 mL. Label "shake well." Stable for 42 days at room temperature (Nahata 2014).

Nahata MC and Pai VB. Pediatric Drug Formulations. 6th ed. Cincinnati, OH: Harvey Whitney Books Co; 2014.

Administration

IV: Administer IV preparation by slow IV infusion over 30 minutes to 3 hours at a final concentration not to exceed 6 mg/mL. Do not administer IM or SubQ. Avoid extravasation.

Oral: Administer on an empty stomach (ie, 1 hour prior to, or 2 hours after meals or antacids) to increase total absorption. The compounded oral suspension must be shaken well before using. May mix contents of capsule with applesauce or jelly.

Storage

Capsule: Store at 25°C (77°F); excursions permitted to 15°C to 30°C (59°F to 86°F); avoid excessive heat.

Injection: Store intact vials at 25°C (77°F); excursions permitted to 15°C to 30°C (59°F to 86°F); avoid excessive heat (>40°C [104°F]). Protect the intact vials from light. Reconstituted vials are stable for 30 hours at room temperature. Stability of parenteral admixture at room temperature (25°C [77°F]) is 8 hours for D5W or 6 hours for NS. Note: As of July 2018, the storage of reconstituted vials was changed from 24 hours to 30 hours at room temperature, the stability when admixed in D5W was changed from 4 hours to 8 hours, and the stability when admixed in NS from 24 hours to 6 hours in the Rifadin prescribing information. Similar changes may not be reflected in the Rifadin prescribing information for product distributed prior to July 2018 or in generic manufacturer's labeling.

Drug Interactions

Abemaciclib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Abemaciclib. Avoid combination

Abiraterone Acetate: CYP3A4 Inducers (Strong) may decrease the serum concentration of Abiraterone Acetate. Management: Avoid whenever possible. If such a combination cannot be avoided, increase abiraterone acetate dosing frequency from once daily to twice daily during concomitant use. Consider therapy modification

Acalabrutinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Acalabrutinib. Management: Avoid co-administration of strong CYP3A inducers in patients taking acalabrutinib. If strong CYP3A inducers cannot be avoided, increase the dose of acalabrutinib to 200 mg twice daily. Consider therapy modification

Afatinib: P-glycoprotein/ABCB1 Inducers may decrease the serum concentration of Afatinib. Management: Increase the afatinib dose by 10 mg as tolerated in patients requiring chronic coadministration of P-gp inducers with afatinib. Reduce afatinib dose back to the original afatinib dose 2 to 3 days after discontinuation of the P-gp inducer. Consider therapy modification

Agomelatine: RifAMPin may decrease the serum concentration of Agomelatine. Monitor therapy

Alfentanil: CYP3A4 Inducers (Strong) may decrease the serum concentration of Alfentanil. Management: If concomitant use of alfentanil and strong CYP3A4 inducers is necessary, consider dosage increase of alfentanil until stable drug effects are achieved. Monitor patients for signs of opioid withdrawal. Consider therapy modification

Aliskiren: P-glycoprotein/ABCB1 Inducers may decrease the serum concentration of Aliskiren. Monitor therapy

Alpelisib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Alpelisib. Avoid combination

Amiodarone: RifAMPin may decrease serum concentrations of the active metabolite(s) of Amiodarone. Specifically, desethylamiodarone concentrations may decrease. RifAMPin may decrease the serum concentration of Amiodarone. Monitor therapy

Antifungal Agents (Azole Derivatives, Systemic): May increase the serum concentration of Rifamycin Derivatives. Only rifabutin appears to be affected. Rifamycin Derivatives may decrease the serum concentration of Antifungal Agents (Azole Derivatives, Systemic). Management: Avoid these combinations when possible. Voriconazole and isavuconazonium are considered contraindicated. Consider therapy modification

Antihepaciviral Combination Products: CYP3A4 Inducers (Strong) may decrease the serum concentration of Antihepaciviral Combination Products. Avoid combination

Apixaban: Inducers of CYP3A4 (Strong) and P-glycoprotein may decrease the serum concentration of Apixaban. Avoid combination

Apremilast: CYP3A4 Inducers (Strong) may decrease the serum concentration of Apremilast. Avoid combination

Aprepitant: CYP3A4 Inducers (Strong) may decrease the serum concentration of Aprepitant. Avoid combination

ARIPiprazole: CYP3A4 Inducers (Strong) may decrease the serum concentration of ARIPiprazole. Management: For indications other than major depressive disorder: double the oral aripiprazole dose over 1 to 2 weeks and closely monitor. Avoid use of strong CYP3A4 inducers for more than 14 days with extended-release injectable aripiprazole. Consider therapy modification

ARIPiprazole Lauroxil: CYP3A4 Inducers (Strong) may decrease serum concentrations of the active metabolite(s) of ARIPiprazole Lauroxil. Management: Patients taking the 441 mg dose of aripiprazole lauroxil increase their dose to 662 mg if used with a strong CYP3A4 inducer for more than 14 days. No dose adjustment is necessary for patients using the higher doses of aripiprazole lauroxil. Consider therapy modification

Artemether: CYP3A4 Inducers (Strong) may decrease serum concentrations of the active metabolite(s) of Artemether. Specifically, dihydroartemisinin concentrations may be reduced. CYP3A4 Inducers (Strong) may decrease the serum concentration of Artemether. Avoid combination

Artesunate: RifAMPin may decrease serum concentrations of the active metabolite(s) of Artesunate. Monitor therapy

Asunaprevir: RifAMPin may decrease the serum concentration of Asunaprevir. This effect is most likely with longer-term coadministration; single-dose rifampin may increase asunaprevir concentrations. RifAMPin may increase the serum concentration of Asunaprevir. This effect is likely following only single-dose or short-term rifampin administration. Longer-term coadministration is likely to result in decreased asunaprevir concentrations. Avoid combination

Ataluren: RifAMPin may decrease the serum concentration of Ataluren. Monitor therapy

Atazanavir: RifAMPin may decrease the serum concentration of Atazanavir. Avoid combination

AtorvaSTATin: RifAMPin may increase the serum concentration of AtorvaSTATin. RifAMPin may decrease the serum concentration of AtorvaSTATin. Management: Administer atorvastatin and rifampin simultaneously if using both. Monitor atorvastatin response closely. Consider therapy modification

Atovaquone: Rifamycin Derivatives may decrease the serum concentration of Atovaquone. Avoid combination

Avanafil: CYP3A4 Inducers (Strong) may decrease the serum concentration of Avanafil. Avoid combination

Avapritinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Avapritinib. Avoid combination

Avatrombopag: RifAMPin may decrease the serum concentration of Avatrombopag. Management: For chronic immune thrombocytopenia, increase initial avatrombopag dose to 40 mg daily. No dosage adjustment needed for patients with chronic liver disease-associated thrombocytopenia using altrombopag prior to a procedure. Consider therapy modification

Axitinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Axitinib. Avoid combination

Barbiturates: Rifamycin Derivatives may increase the metabolism of Barbiturates. Monitor therapy

Bazedoxifene: RifAMPin may decrease the serum concentration of Bazedoxifene. This may lead to loss of efficacy or, if bazedoxifene is combined with estrogen therapy, an increased risk of endometrial hyperplasia. Monitor therapy

BCG (Intravesical): Antibiotics may diminish the therapeutic effect of BCG (Intravesical). Avoid combination

BCG Vaccine (Immunization): Antibiotics may diminish the therapeutic effect of BCG Vaccine (Immunization). Monitor therapy

Bedaquiline: CYP3A4 Inducers (Strong) may decrease the serum concentration of Bedaquiline. Avoid combination

Benperidol: CYP3A4 Inducers (Strong) may decrease the serum concentration of Benperidol. Monitor therapy

Benzhydrocodone: CYP3A4 Inducers (Strong) may decrease the serum concentration of Benzhydrocodone. Specifically, the serum concentrations of hydrocodone may be reduced. Monitor therapy

Beta-Blockers: Rifamycin Derivatives may decrease the serum concentration of Beta-Blockers. Monitor therapy

Betamethasone (Systemic): CYP3A4 Inducers (Strong) may decrease the serum concentration of Betamethasone (Systemic). Monitor therapy

Betrixaban: P-glycoprotein/ABCB1 Inducers may decrease the serum concentration of Betrixaban. Avoid combination

Bictegravir: RifAMPin may decrease the serum concentration of Bictegravir. Avoid combination

Bisoprolol: CYP3A4 Inducers (Strong) may decrease the serum concentration of Bisoprolol. Monitor therapy

Blonanserin: CYP3A4 Inducers (Strong) may decrease the serum concentration of Blonanserin. Monitor therapy

Bortezomib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Bortezomib. Avoid combination

Bosentan: RifAMPin may decrease the serum concentration of Bosentan. Following the initial week of concurrent rifampin, this effect is most likely. RifAMPin may increase the serum concentration of Bosentan. This effect is most likely to be observed within the initial few days of concurrent therapy (and may be greatest immediately following initiation of the combination). Monitor therapy

Bosutinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Bosutinib. Avoid combination

Brentuximab Vedotin: CYP3A4 Inducers (Strong) may decrease the serum concentration of Brentuximab Vedotin. Specifically, concentrations of the active monomethyl auristatin E (MMAE) component may be decreased. Monitor therapy

Brexpiprazole: CYP3A4 Inducers (Strong) may decrease the serum concentration of Brexpiprazole. Management: If brexpiprazole is used together with a strong CYP3A4 inducer, the brexpiprazole dose should gradually be doubled over the course of 1 to 2 weeks. Decrease brexpiprazole to original dose over 1 to 2 weeks if the strong CYP3A4 inducer is discontinued. Consider therapy modification

Brigatinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Brigatinib. Avoid combination

Brivaracetam: CYP2C19 Inducers (Strong) may decrease the serum concentration of Brivaracetam. Management: Increase the brivaracetam dose by up to 100% (ie, double the dose) if used with rifampin and consider the same dose adjustment if used with other strong CYP2C19 inducers. Monitor for reduced brivaracetam efficacy. Consider therapy modification

Bromocriptine: CYP3A4 Inducers (Strong) may decrease the serum concentration of Bromocriptine. Monitor therapy

Bromperidol: CYP3A4 Inducers (Strong) may decrease the serum concentration of Bromperidol. Monitor therapy

Buprenorphine: CYP3A4 Inducers (Strong) may decrease the serum concentration of Buprenorphine. Monitor therapy

BuPROPion: CYP2B6 Inducers (Moderate) may decrease the serum concentration of BuPROPion. Monitor therapy

BusPIRone: CYP3A4 Inducers (Strong) may decrease the serum concentration of BusPIRone. Management: Consider alternatives to this combination. If coadministration of these agents is deemed necessary, monitor patients for reduced buspirone effects and increase buspirone doses as needed. Consider therapy modification

Cabazitaxel: CYP3A4 Inducers (Strong) may decrease the serum concentration of Cabazitaxel. Monitor therapy

Cabozantinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Cabozantinib. Management: Avoid use of strong CYP3A4 inducers with cabozantinib if possible. If combined, increase cabozantinib capsules (Cometriq) by 40 mg from previous dose, max 180 mg daily. Increase cabozantinib tablets (Cabometyx) by 20 mg from previous dose, max 80 mg daily Consider therapy modification

Calcifediol: CYP3A4 Inducers (Strong) may decrease the serum concentration of Calcifediol. Monitor therapy

Calcium Channel Blockers: Rifamycin Derivatives may decrease the serum concentration of Calcium Channel Blockers. This primarily affects oral forms of calcium channel blockers. Management: The labeling for some US and Canadian calcium channel blockers (CCBs) contraindicate use with rifampin, however recommendations vary. Consult appropriate labeling. If coadministered, monitor for decreased CCB efficiacy. Consider therapy modification

Canagliflozin: RifAMPin may decrease the serum concentration of Canagliflozin. Management: Consider increasing canagliflozin dose to 200 mg/day in patients tolerating 100 mg/day. A further increase to 300 mg/day can be considered in patients with an estimated glomerular filtration rate (GFR) of 60 mL/min/1.73 m2 or greater. Consider therapy modification

Cannabidiol: CYP3A4 Inducers (Strong) may decrease the serum concentration of Cannabidiol. Monitor therapy

Cannabidiol: CYP2C19 Inducers (Strong) may decrease the serum concentration of Cannabidiol. Monitor therapy

Cannabis: CYP3A4 Inducers (Strong) may decrease the serum concentration of Cannabis. More specifically, tetrahydrocannabinol and cannabidiol serum concentrations may be decreased. Monitor therapy

Capmatinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Capmatinib. Avoid combination

CarBAMazepine: CYP3A4 Inducers (Strong) may decrease the serum concentration of CarBAMazepine. Monitor therapy

Cariprazine: CYP3A4 Inducers (Strong) may decrease the serum concentration of Cariprazine. Avoid combination

Carisoprodol: CYP2C19 Inducers (Strong) may increase serum concentrations of the active metabolite(s) of Carisoprodol. CYP2C19 Inducers (Strong) may decrease the serum concentration of Carisoprodol. Monitor therapy

Carvedilol: RifAMPin may decrease the serum concentration of Carvedilol. Monitor therapy

Caspofungin: RifAMPin may decrease the serum concentration of Caspofungin. Management: Caspofungin prescribing information recommends using a dose of 70 mg daily in adults (or 70 mg/m2, up to a maximum of 70 mg, daily in pediatric patients) who are also receiving rifampin. Consider therapy modification

CeFAZolin: May enhance the adverse/toxic effect of RifAMPin. Specifically, the risk for bleeding may be increased. Management: Avoid concomitant use of rifampin with cefazolin when possible. If combined, closely monitor prothrombin time or other coagulation tests and administer vitamin K as needed. Consider therapy modification

Celecoxib: CYP2C9 Inducers (Moderate) may decrease the serum concentration of Celecoxib. Monitor therapy

Celiprolol: P-glycoprotein/ABCB1 Inducers may decrease the serum concentration of Celiprolol. Monitor therapy

Cephalosporins (N-methylthiotetrazole [NMTT] Side Chain Containing): May enhance the adverse/toxic effect of RifAMPin. Specifically, the risk for bleeding may be increased. Management: Avoid concomitant use of rifampin with cephalosporins that contain an N-methylthiotetrazole (NMTT) side chain when possible. If combined, closely monitor prothrombin time or other coagulation tests and administer vitamin K as needed. Consider therapy modification

Ceritinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Ceritinib. Avoid combination

Chloramphenicol (Systemic): RifAMPin may increase the metabolism of Chloramphenicol (Systemic). Monitor therapy

ChlorproPAMIDE: CYP3A4 Inducers (Strong) may decrease the serum concentration of ChlorproPAMIDE. Monitor therapy

Cholera Vaccine: Antibiotics may diminish the therapeutic effect of Cholera Vaccine. Management: Avoid cholera vaccine in patients receiving systemic antibiotics, and within 14 days following the use of oral or parenteral antibiotics. Avoid combination

Citalopram: RifAMPin may decrease the serum concentration of Citalopram. Monitor therapy

Cladribine: BCRP/ABCG2 Inducers may decrease the serum concentration of Cladribine. Monitor therapy

Cladribine: P-glycoprotein/ABCB1 Inducers may decrease the serum concentration of Cladribine. Monitor therapy

Clarithromycin: CYP3A4 Inducers (Strong) may increase serum concentrations of the active metabolite(s) of Clarithromycin. Clarithromycin may increase the serum concentration of CYP3A4 Inducers (Strong). CYP3A4 Inducers (Strong) may decrease the serum concentration of Clarithromycin. Management: Consider alternative antimicrobial therapy for patients receiving a CYP3A inducer. Drugs that enhance the metabolism of clarithromycin into 14-hydroxyclarithromycin may alter the clinical activity of clarithromycin and may impair clarithromycin efficacy. Consider therapy modification

Clopidogrel: CYP2C19 Inducers (Strong) may increase serum concentrations of the active metabolite(s) of Clopidogrel. Monitor therapy

CloZAPine: CYP3A4 Inducers (Strong) may decrease the serum concentration of CloZAPine. Management: Avoid use with strong CYP3A4 inducers when possible. If combined, monitor patients closely and consider clozapine dose increases. Clozapine dose reduction and further monitoring may be required when strong CYP3A4 inducers are discontinued. Consider therapy modification

Cobicistat: RifAMPin may decrease the serum concentration of Cobicistat. Avoid combination

Cobimetinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Cobimetinib. Avoid combination

Codeine: CYP3A4 Inducers (Strong) may decrease serum concentrations of the active metabolite(s) of Codeine. Monitor therapy

Copanlisib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Copanlisib. Avoid combination

Crizotinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Crizotinib. Avoid combination

Cyclophosphamide: CYP2B6 Inducers (Moderate) may increase serum concentrations of the active metabolite(s) of Cyclophosphamide. Monitor therapy

CycloSPORINE (Systemic): CYP3A4 Inducers (Strong) may decrease the serum concentration of CycloSPORINE (Systemic). Management: Monitor closely for reduced cyclosporine concentrations when combined with strong CYP3A4 inducers. Cyclosporine dose increases will likely be required to maintain adequate serum concentrations. Consider therapy modification

CYP3A4 Substrates (High risk with Inducers): CYP3A4 Inducers (Strong) may increase the metabolism of CYP3A4 Substrates (High risk with Inducers). Management: Consider an alternative for one of the interacting drugs. Some combinations may be specifically contraindicated. Consult appropriate manufacturer labeling. Consider therapy modification

Dabigatran Etexilate: P-glycoprotein/ABCB1 Inducers may decrease the serum concentration of Dabigatran Etexilate. Management: Avoid concurrent use of dabigatran with P-glycoprotein inducers whenever possible. Avoid combination

Dabrafenib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Dabrafenib. Monitor therapy

Daclatasvir: CYP3A4 Inducers (Strong) may decrease the serum concentration of Daclatasvir. Avoid combination

Dapsone (Systemic): CYP3A4 Inducers (Strong) may decrease the serum concentration of Dapsone (Systemic). Monitor therapy

Darolutamide: Inducers of CYP3A4 (Strong) and P-glycoprotein may decrease the serum concentration of Darolutamide. Avoid combination

Darunavir: RifAMPin may decrease the serum concentration of Darunavir. Avoid combination

Dasabuvir: CYP3A4 Inducers (Strong) may decrease the serum concentration of Dasabuvir. Avoid combination

Dasatinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Dasatinib. Management: Avoid when possible. If such a combination cannot be avoided, consider increasing dasatinib dose and monitor clinical response and toxicity closely. Consider therapy modification

Deferasirox: RifAMPin may decrease the serum concentration of Deferasirox. Management: Avoid combination when possible; if the combination must be used, consider a 50% increase in initial deferasirox dose, with monitoring of serum ferritin concentrations and clinical responses to guide further dosing. Consider therapy modification

Deflazacort: CYP3A4 Inducers (Strong) may decrease serum concentrations of the active metabolite(s) of Deflazacort. Avoid combination

Delamanid: CYP3A4 Inducers (Strong) may decrease the serum concentration of Delamanid. Avoid combination

Delavirdine: Rifamycin Derivatives may increase the metabolism of Delavirdine. Delavirdine may increase the serum concentration of Rifamycin Derivatives. Specifically, Rifabutin serum concentration may be increased. Avoid combination

DexAMETHasone (Systemic): CYP3A4 Inducers (Strong) may decrease the serum concentration of DexAMETHasone (Systemic). Management: Consider dexamethasone dose increases in patients receiving strong CYP3A4 inducers and monitor closely for reduced dexamethasone efficacy. Consider avoiding this combination when treating life threatening conditions (ie, multiple myeloma). Consider therapy modification

Dexlansoprazole: CYP2C19 Inducers (Strong) may decrease the serum concentration of Dexlansoprazole. Avoid combination

Diclofenac (Systemic): CYP2C9 Inducers (Moderate) may decrease the serum concentration of Diclofenac (Systemic). Monitor therapy

Dienogest: CYP3A4 Inducers (Strong) may decrease the serum concentration of Dienogest. Avoid combination

Diethylstilbestrol: CYP3A4 Inducers (Strong) may decrease the serum concentration of Diethylstilbestrol. Monitor therapy

Digitoxin: P-glycoprotein/ABCB1 Inducers may decrease the serum concentration of Digitoxin. Monitor therapy

Digoxin: P-glycoprotein/ABCB1 Inducers may decrease the serum concentration of Digoxin. Monitor therapy

DilTIAZem: RifAMPin may decrease the serum concentration of DilTIAZem. Avoid combination

Disopyramide: RifAMPin may decrease the serum concentration of Disopyramide. Monitor therapy

Dolutegravir: RifAMPin may decrease the serum concentration of Dolutegravir. Management: Increase dolutegravir to 50 mg twice/day in adults. Increase weight based dose to twice daily in pediatric patients. See interaction monograph for details. Seek alternative to rifampin if suspected INSTI resistance. Consider therapy modification

Doravirine: CYP3A4 Inducers (Strong) may decrease the serum concentration of Doravirine. Avoid combination

Doxercalciferol: CYP3A4 Inducers (Strong) may increase serum concentrations of the active metabolite(s) of Doxercalciferol. Monitor therapy

DOXOrubicin (Conventional): P-glycoprotein/ABCB1 Inducers may decrease the serum concentration of DOXOrubicin (Conventional). Avoid combination

Doxycycline: RifAMPin may decrease the serum concentration of Doxycycline. Monitor therapy

Dronabinol: CYP3A4 Inducers (Strong) may decrease the serum concentration of Dronabinol. Monitor therapy

Dronedarone: CYP3A4 Inducers (Strong) may decrease the serum concentration of Dronedarone. Avoid combination

Duvelisib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Duvelisib. Avoid combination

Edoxaban: RifAMPin may decrease the serum concentration of Edoxaban. Avoid combination

Efavirenz: RifAMPin may decrease the serum concentration of Efavirenz. Management: Closely monitor virologic response to efavirenz when used with rifampin. Guidelines suggest no efavirenz dose adjustments are required when combined, while labeling recommends an efavirenz dose increase to 800 mg daily in adults weighing more than 50 kg. Monitor therapy

Elagolix: RifAMPin may increase the serum concentration of Elagolix. Management: Use of the elagolix 200 mg twice daily dose with rifampin is not recommended. Limit combined use of the elagolix 150 mg once daily dose with rifampin to a maximum of 6 months. Consider therapy modification

Elagolix, Estradiol, and Norethindrone: May increase the serum concentration of RifAMPin. Specifically, rifampin may increase elagolix concentrations and decrease estradiol and norethindrone concentrations. Avoid combination

Elbasvir: CYP3A4 Inducers (Strong) may decrease the serum concentration of Elbasvir. Avoid combination

Elexacaftor, Tezacaftor, and Ivacaftor: CYP3A4 Inducers (Strong) may decrease the serum concentration of Elexacaftor, Tezacaftor, and Ivacaftor. Avoid combination

Eliglustat: CYP3A4 Inducers (Strong) may decrease the serum concentration of Eliglustat. Avoid combination

Eltrombopag: May increase the serum concentration of OATP1B1/1B3 (SLCO1B1/1B3) Substrates. Monitor therapy

Eluxadoline: OATP1B1/1B3 (SLCO1B1/1B3) Inhibitors may increase the serum concentration of Eluxadoline. Management: Decrease the eluxadoline dose to 75 mg twice daily if combined with OATP1B1/1B3 inhibitors and monitor patients for increased eluxadoline effects/toxicities. Consider therapy modification

Elvitegravir: RifAMPin may decrease the serum concentration of Elvitegravir. Avoid combination

Encorafenib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Encorafenib. Avoid combination

Enfortumab Vedotin: CYP3A4 Inducers (Strong) may decrease the serum concentration of Enfortumab Vedotin. Specifically, concentrations of the active monomethyl auristatin E (MMAE) component may be decreased. Monitor therapy

Entrectinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Entrectinib. Avoid combination

Enzalutamide: CYP3A4 Inducers (Strong) may decrease the serum concentration of Enzalutamide. Management: Consider using an alternative agent that has no or minimal CYP3A4 induction potential when possible. If this combination cannot be avoided, increase the dose of enzalutamide from 160 mg daily to 240 mg daily. Consider therapy modification

Eravacycline: CYP3A4 Inducers (Strong) may decrease the serum concentration of Eravacycline. Management: Increase the eravacycline dose to 1.5 mg/kg every 12 hours when combined with strong CYP3A4 inducers. Consider therapy modification

Erdafitinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Erdafitinib. Avoid combination

Erlotinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Erlotinib. Management: Avoid combination if possible. If combination must be used, increase erlotinib dose by 50 mg increments every 2 weeks as tolerated, to a maximum of 450 mg/day. Consider therapy modification

Escitalopram: RifAMPin may decrease the serum concentration of Escitalopram. Monitor therapy

Esomeprazole: CYP2C19 Inducers (Strong) may decrease the serum concentration of Esomeprazole. Avoid combination

Estriol (Systemic): CYP3A4 Inducers (Strong) may decrease the serum concentration of Estriol (Systemic). Monitor therapy

Estriol (Topical): CYP3A4 Inducers (Strong) may decrease the serum concentration of Estriol (Topical). Monitor therapy

Estrogen Derivatives (Contraceptive): Rifamycin Derivatives may decrease the serum concentration of Estrogen Derivatives (Contraceptive). Contraceptive failure is possible. Management: Contraceptive failure is possible. Use of an alternative, nonhormonal contraceptive is recommended. Consider therapy modification

Etizolam: CYP3A4 Inducers (Strong) may decrease the serum concentration of Etizolam. Monitor therapy

Etoposide: CYP3A4 Inducers (Strong) may decrease the serum concentration of Etoposide. Management: When possible, seek alternatives to strong CYP3A4-inducing medications in patients receiving etoposide. If combined, monitor patients closely for diminished etoposide response and need for etoposide dose increases. Consider therapy modification

Etoposide Phosphate: CYP3A4 Inducers (Strong) may decrease the serum concentration of Etoposide Phosphate. Management: When possible, seek alternatives to strong CYP3A4-inducing medications in patients receiving etoposide phosphate. If these combinations cannot be avoided, monitor patients closely for diminished etoposide phosphate response. Consider therapy modification

Etravirine: CYP3A4 Inducers (Strong) may decrease the serum concentration of Etravirine. Avoid combination

Everolimus: Inducers of CYP3A4 (Strong) and P-glycoprotein may decrease the serum concentration of Everolimus. Management: Afinitor: Double the everolimus daily dose, using increments of 5 mg or less, with careful monitoring; multiple increments may be necessary. Zortress: Avoid if possible and monitor for decreased everolimus concentrations if combined. Consider therapy modification

Evogliptin: CYP3A4 Inducers (Strong) may decrease the serum concentration of Evogliptin. Monitor therapy

Exemestane: CYP3A4 Inducers (Strong) may decrease the serum concentration of Exemestane. Management: Increase the exemestane dose to 50 mg/day in patients receiving concurrent strong CYP3A4 inducers. Monitor patients closely for evidence of toxicity or inadequate clinical response. Consider therapy modification

Fedratinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Fedratinib. Avoid combination

Fenfluramine: RifAMPin may decrease the serum concentration of Fenfluramine. Management: Consider increasing the fenfluramine dose when used together with rifampin, but do not exceed the fenfluramine maximum daily dosage [0.35 mg/kg twice daily (26 mg/day)]. Monitor therapy

FentaNYL: CYP3A4 Inducers (Strong) may decrease the serum concentration of FentaNYL. Monitor therapy

Fexofenadine: RifAMPin may decrease the serum concentration of Fexofenadine. RifAMPin may increase the serum concentration of Fexofenadine. Monitor therapy

Fimasartan: RifAMPin may increase the serum concentration of Fimasartan. Avoid combination

Flibanserin: CYP3A4 Inducers (Strong) may decrease the serum concentration of Flibanserin. Avoid combination

Fluvastatin: RifAMPin may decrease the serum concentration of Fluvastatin. Specifically, this occurs with prolonged coadministration. RifAMPin may increase the serum concentration of Fluvastatin. Specifically, this occurs upon rifampin initiation. Monitor therapy

Fosamprenavir: RifAMPin may decrease the serum concentration of Fosamprenavir. Specifically, concentrations of amprenavir (active metabolite) may be decreased. Avoid combination

Fosaprepitant: CYP3A4 Inducers (Strong) may decrease the serum concentration of Fosaprepitant. Specifically, CYP3A4 Inducers (Strong) may decrease serum concentrations of the active metabolite aprepitant. Avoid combination

Fosnetupitant: CYP3A4 Inducers (Strong) may decrease serum concentrations of the active metabolite(s) of Fosnetupitant. Avoid combination

Fosphenytoin-Phenytoin: CYP2C19 Inducers (Strong) may decrease the serum concentration of Fosphenytoin-Phenytoin. Monitor therapy

Fostamatinib: CYP3A4 Inducers (Strong) may decrease serum concentrations of the active metabolite(s) of Fostamatinib. Avoid combination

Fostemsavir: CYP3A4 Inducers (Strong) may decrease serum concentrations of the active metabolite(s) of Fostemsavir. Avoid combination

Gefitinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Gefitinib. Management: In the absence of severe adverse reactions, increase gefitinib dose to 500 mg daily in patients receiving strong CYP3A4 inducers; resume 250 mg dose 7 days after discontinuation of the strong inducer. Carefully monitor clinical response. Consider therapy modification

Gemfibrozil: May increase the serum concentration of OATP1B1/1B3 (SLCO1B1/1B3) Substrates. See separate drug interaction monographs for agents listed as exceptions. Monitor therapy

Gemigliptin: CYP3A4 Inducers (Strong) may decrease serum concentrations of the active metabolite(s) of Gemigliptin. CYP3A4 Inducers (Strong) may decrease the serum concentration of Gemigliptin. Avoid combination

Gestrinone: RifAMPin may decrease the serum concentration of Gestrinone. Monitor therapy

Gilteritinib: Inducers of CYP3A4 (Strong) and P-glycoprotein may decrease the serum concentration of Gilteritinib. Avoid combination

Glasdegib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Glasdegib. Avoid combination

Glecaprevir and Pibrentasvir: RifAMPin may decrease the serum concentration of Glecaprevir and Pibrentasvir. RifAMPin may increase the serum concentration of Glecaprevir and Pibrentasvir. Specifically, a single dose of rifampin may increase glecaprevir/pibrentasvir concentrations, while chronic daily use of rifampin may decrease glecaprevir/pibrentasvir concentrations. Avoid combination

Grazoprevir: RifAMPin may decrease the serum concentration of Grazoprevir. Conversely, single doses of Rifampin may increase Grazoprevir concentrations. Avoid combination

GuanFACINE: CYP3A4 Inducers (Strong) may decrease the serum concentration of GuanFACINE. Management: Increase extended-release guanfacine dose by up to double when initiating guanfacine in patients taking CYP3A4 inducers or if initiating a CYP3A4 inducer in a patient already taking extended-release guanfacine. Monitor for reduced guanfacine efficacy. Consider therapy modification

HMG-CoA Reductase Inhibitors (Statins): Rifamycin Derivatives may decrease the serum concentration of HMG-CoA Reductase Inhibitors (Statins). Management: Consider use of noninteracting antilipemic agents (note: pitavastatin concentrations may increase with rifamycin treatment). Monitor for altered HMG-CoA reductase inhibitor effects. Rifabutin and fluvastatin, or possibly pravastatin, may pose lower risk. Consider therapy modification

HYDROcodone: CYP3A4 Inducers (Strong) may decrease the serum concentration of HYDROcodone. Monitor therapy

Hydrocortisone (Systemic): CYP3A4 Inducers (Strong) may decrease the serum concentration of Hydrocortisone (Systemic). Monitor therapy

Ibrutinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Ibrutinib. Avoid combination

Idelalisib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Idelalisib. Avoid combination

Ifosfamide: CYP3A4 Inducers (Strong) may increase serum concentrations of the active metabolite(s) of Ifosfamide. CYP3A4 Inducers (Strong) may decrease serum concentrations of the active metabolite(s) of Ifosfamide. Monitor therapy

Imatinib: Rifamycin Derivatives may decrease the serum concentration of Imatinib. Management: Avoid concurrent use of imatinib with the rifamycin derivatives when possible. If such a combination must be used, increase imatinib dose by at least 50% and monitor the patient's clinical response closely. Consider therapy modification

Imatinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Imatinib. Management: Avoid concurrent use of imatinib with strong CYP3A4 inducers when possible. If such a combination must be used, increase imatinib dose by at least 50% and monitor the patient's clinical response closely. Consider therapy modification

Indinavir: RifAMPin may decrease the serum concentration of Indinavir. Avoid combination

Irinotecan Products: CYP3A4 Inducers (Strong) may decrease serum concentrations of the active metabolite(s) of Irinotecan Products. Specifically, serum concentrations of SN-38 may be reduced. CYP3A4 Inducers (Strong) may decrease the serum concentration of Irinotecan Products. Avoid combination

Isavuconazonium Sulfate: CYP3A4 Inducers (Strong) may decrease serum concentrations of the active metabolite(s) of Isavuconazonium Sulfate. Specifically, CYP3A4 Inducers (Strong) may decrease isavuconazole serum concentrations. Avoid combination

Isoniazid: Rifamycin Derivatives may enhance the hepatotoxic effect of Isoniazid. Even so, this is a frequently employed combination regimen. Monitor therapy

Istradefylline: CYP3A4 Inducers (Strong) may decrease the serum concentration of Istradefylline. Avoid combination

Itraconazole: CYP3A4 Inducers (Strong) may decrease the serum concentration of Itraconazole. Avoid combination

Ivabradine: CYP3A4 Inducers (Strong) may decrease the serum concentration of Ivabradine. Avoid combination

Ivacaftor: CYP3A4 Inducers (Strong) may decrease the serum concentration of Ivacaftor. Avoid combination

Ivosidenib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Ivosidenib. Avoid combination

Ixabepilone: CYP3A4 Inducers (Strong) may decrease the serum concentration of Ixabepilone. Management: Avoid this combination whenever possible. If this combination must be used, a gradual increase in ixabepilone dose from 40 mg/m2 to 60 mg/m2 (given as a 4-hour infusion), as tolerated, should be considered. Consider therapy modification

Ixazomib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Ixazomib. Avoid combination

Ketamine: CYP2B6 Inducers (Moderate) may decrease the serum concentration of Ketamine. Monitor therapy

Ketoconazole (Systemic): CYP3A4 Inducers (Strong) may decrease the serum concentration of Ketoconazole (Systemic). Management: The use of ketoconazole concurrently with or within 2 weeks of a strong CYP3A4 inducer is not recommended. If such a combination cannot be avoided, monitor patients closely for evidence of diminished clinical response to ketoconazole. Consider therapy modification

Lactobacillus and Estriol: Antibiotics may diminish the therapeutic effect of Lactobacillus and Estriol. Monitor therapy

LamoTRIgine: RifAMPin may decrease the serum concentration of LamoTRIgine. Management: For patients taking rifampin without valproate, lamotrigine dose adjustments are recommended for lamotrigine initiation. Recommendations vary based on lamotrigine indication and age. See full interact monograph for details. Consider therapy modification

Lansoprazole: CYP2C19 Inducers (Strong) may decrease the serum concentration of Lansoprazole. Avoid combination

Lapatinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Lapatinib. Management: If concomitant use cannot be avoided, titrate lapatinib gradually from 1,250 mg/day up to 4,500 mg/day (HER2 positive metastatic breast cancer) or 1,500 mg/day up to 5,500 mg/day (hormone receptor/HER2 positive breast cancer) as tolerated. Consider therapy modification

Larotrectinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Larotrectinib. Management: Avoid use of strong CYP3A4 inducers with larotrectinib. If this combination cannot be avoided, double the larotrectinib dose. Reduced to previous dose after stopping the inducer after a period of 3 to 5 times the inducer's half-life. Consider therapy modification

Ledipasvir: P-glycoprotein/ABCB1 Inducers may decrease the serum concentration of Ledipasvir. Avoid combination

Lefamulin: CYP3A4 Inducers (Strong) may decrease the serum concentration of Lefamulin. Management: Avoid concomitant use of lefamulin with strong CYP3A4 inducers unless the benefits outweigh the risks. Consider therapy modification

Lefamulin: P-glycoprotein/ABCB1 Inducers may decrease the serum concentration of Lefamulin. Management: Avoid concomitant use of lefamulin with P-glycoprotein/ABCB1 inducers unless the benefits outweigh the risks. Consider therapy modification

Lefamulin (Intravenous): CYP3A4 Inducers (Strong) may decrease the serum concentration of Lefamulin (Intravenous). Management: Avoid concomitant use of lefamulin intravenous infusion with strong CYP3A4 inducers unless the benefits outweigh the risks. Consider therapy modification

Lefamulin (Intravenous): P-glycoprotein/ABCB1 Inducers may decrease the serum concentration of Lefamulin (Intravenous). Management: Avoid concomitant use of lefamulin (intravenous) with P-glycoprotein/ABCB1 inducers unless the benefits outweigh the risks. Consider therapy modification

Leflunomide: RifAMPin may increase serum concentrations of the active metabolite(s) of Leflunomide. Monitor therapy

Lemborexant: CYP3A4 Inducers (Strong) may decrease the serum concentration of Lemborexant. Avoid combination

Lesinurad: CYP2C9 Inducers (Moderate) may decrease the serum concentration of Lesinurad. Monitor therapy

Letermovir: P-glycoprotein/ABCB1 Inducers may decrease the serum concentration of Letermovir. Avoid combination

Letermovir: May increase the serum concentration of UGT1A1 Inducers. Avoid combination

Levomethadone: RifAMPin may decrease the serum concentration of Levomethadone. Monitor therapy

Levonorgestrel (IUD): CYP3A4 Inducers (Strong) may diminish the therapeutic effect of Levonorgestrel (IUD). CYP3A4 Inducers (Strong) may decrease the serum concentration of Levonorgestrel (IUD). Monitor therapy

LinaGLIPtin: CYP3A4 Inducers (Strong) may decrease the serum concentration of LinaGLIPtin. Management: Strongly consider using an alternative to any strong CYP3A4 inducer in patients who are being treated with linagliptin. If this combination is used, monitor patients closely for evidence of reduced linagliptin effectiveness. Consider therapy modification

LinaGLIPtin: P-glycoprotein/ABCB1 Inducers may decrease the serum concentration of LinaGLIPtin. Management: Strongly consider using an alternative to any P-glycoprotein inducer in patients who are being treated with linagliptin. If this combination is used, monitor patients closely for evidence of reduced linagliptin effectiveness. Consider therapy modification

Lopinavir: RifAMPin may enhance the adverse/toxic effect of Lopinavir. Specifically, the risk of hepatocellular toxicity may be increased. RifAMPin may decrease the serum concentration of Lopinavir. Avoid combination

Lorlatinib: CYP3A4 Inducers (Strong) may enhance the hepatotoxic effect of Lorlatinib. CYP3A4 Inducers (Strong) may decrease the serum concentration of Lorlatinib. Avoid combination

Lornoxicam: CYP2C9 Inducers (Moderate) may decrease the serum concentration of Lornoxicam. Monitor therapy

Losartan: RifAMPin may decrease the serum concentration of Losartan. Monitor therapy

Lumacaftor and Ivacaftor: CYP3A4 Inducers (Strong) may decrease the serum concentration of Lumacaftor and Ivacaftor. Specifically, the serum concentration of ivacaftor may be decreased. Avoid combination

Lumateperone: CYP3A4 Inducers (Strong) may decrease the serum concentration of Lumateperone. Avoid combination

Lumefantrine: CYP3A4 Inducers (Strong) may decrease the serum concentration of Lumefantrine. Avoid combination

Lurasidone: CYP3A4 Inducers (Strong) may decrease the serum concentration of Lurasidone. Avoid combination

Lurbinectedin: CYP3A4 Inducers (Strong) may decrease the serum concentration of Lurbinectedin. Avoid combination

Macimorelin: CYP3A4 Inducers (Strong) may decrease the serum concentration of Macimorelin. Avoid combination

Macitentan: CYP3A4 Inducers (Strong) may decrease the serum concentration of Macitentan. Avoid combination

Manidipine: CYP3A4 Inducers (Strong) may decrease the serum concentration of Manidipine. Management: Consider avoiding concomitant use of manidipine and strong CYP3A4 inducers. If combined, monitor closely for decreased manidipine effects and loss of efficacy. Increased manidipine doses may be required. Consider therapy modification

Maraviroc: CYP3A4 Inducers (Strong) may decrease the serum concentration of Maraviroc. Management: Increase maraviroc adult dose to 600mg twice/day, but only in the absence of a concurrent strong CYP3A4 inhibitor. Not recommended for pediatric patients not also receiving a strong CYP3A4 inhibitor. Do not use in patients with CrCl less than 30 mL/min. Consider therapy modification

Meperidine: CYP3A4 Inducers (Strong) may decrease the serum concentration of Meperidine. Monitor therapy

Methadone: Rifamycin Derivatives may decrease the serum concentration of Methadone. Management: Seek alternatives when possible. If used concomitantly, monitor closely for symptoms of methadone withdrawal upon rifamycin derivative initiation, and for excess sedation upon rifamycin derivative discontinuation. Consider therapy modification

MethylPREDNISolone: CYP3A4 Inducers (Strong) may decrease the serum concentration of MethylPREDNISolone. Management: Consider methylprednisolone dose increases in patients receiving strong CYP3A4 inducers and monitor closely for reduced steroid efficacy. Consider therapy modification

Midostaurin: CYP3A4 Inducers (Strong) may decrease the serum concentration of Midostaurin. Avoid combination

MiFEPRIStone: CYP3A4 Inducers (Strong) may decrease the serum concentration of MiFEPRIStone. Avoid combination

Mirabegron: RifAMPin may decrease the serum concentration of Mirabegron. Monitor therapy

Mirodenafil: CYP3A4 Inducers (Strong) may decrease the serum concentration of Mirodenafil. Management: Consider avoiding the concomitant use of mirodenafil and strong CYP3A4 inducers. If combined, monitor for decreased mirodenafil effects. Mirodenafil dose increases may be required to achieve desired effects. Consider therapy modification

Mirtazapine: CYP3A4 Inducers (Strong) may decrease the serum concentration of Mirtazapine. Monitor therapy

Morphine (Systemic): RifAMPin may decrease the serum concentration of Morphine (Systemic). Monitor therapy

Mycophenolate: Rifamycin Derivatives may decrease the serum concentration of Mycophenolate. Specifically, rifamycin derivatives may decrease the concentration of the active metabolite mycophenolic acid. Avoid combination

Naldemedine: CYP3A4 Inducers (Strong) may decrease the serum concentration of Naldemedine. Avoid combination

Nalmefene: RifAMPin may decrease the serum concentration of Nalmefene. Monitor therapy

Naloxegol: CYP3A4 Inducers (Strong) may decrease the serum concentration of Naloxegol. Avoid combination

Nateglinide: CYP3A4 Inducers (Strong) may decrease the serum concentration of Nateglinide. Monitor therapy

Nelfinavir: RifAMPin may decrease the serum concentration of Nelfinavir. Avoid combination

Neratinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Neratinib. Avoid combination

Netupitant: CYP3A4 Inducers (Strong) may decrease the serum concentration of Netupitant. Avoid combination

Nevirapine: RifAMPin may decrease the serum concentration of Nevirapine. Management: Avoid whenever possible. When this combination is necessary, use immediate-release nevirapine (avoid extended-release nevirapine) at a dose of 200 mg twice daily with no lead-in (per adult/adolescent HIV guidelines). Monitor nevirapine response closely. Consider therapy modification

NIFEdipine: CYP3A4 Inducers (Strong) may decrease the serum concentration of NIFEdipine. Avoid combination

Nilotinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Nilotinib. Avoid combination

NiMODipine: CYP3A4 Inducers (Strong) may decrease the serum concentration of NiMODipine. Avoid combination

Nintedanib: Inducers of CYP3A4 (Strong) and P-glycoprotein may decrease the serum concentration of Nintedanib. Avoid combination

Nisoldipine: CYP3A4 Inducers (Strong) may decrease the serum concentration of Nisoldipine. Avoid combination

Nitrazepam: RifAMPin may decrease the serum concentration of Nitrazepam. Management: Monitor closely for reduced effects of nitrazepam. When possible, consider alternatives to one of these drugs, or increases in initial nitrazepam doses. Consider therapy modification

OLANZapine: RifAMPin may decrease the serum concentration of OLANZapine. Monitor therapy

Olaparib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Olaparib. Avoid combination

Oliceridine: CYP3A4 Inducers (Strong) may decrease the serum concentration of Oliceridine. Monitor therapy

Omeprazole: CYP2C19 Inducers (Strong) may decrease the serum concentration of Omeprazole. Avoid combination

Osilodrostat: CYP3A4 Inducers (Strong) may decrease the serum concentration of Osilodrostat. Monitor therapy

Osimertinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Osimertinib. Management: Avoid coadministration of osimertinib and strong CYP3A4 inducers if possible. If coadministration is unavoidable, increase osimertinib to 160 mg daily. Reduce osimertinib to 80 mg daily 3 weeks after discontinuation of the strong CYP3A4 inducer. Consider therapy modification

Ospemifene: RifAMPin may decrease the serum concentration of Ospemifene. Monitor therapy

OXcarbazepine: CYP3A4 Inducers (Strong) may decrease the serum concentration of OXcarbazepine. Specifically, the concentrations of the 10-monohydroxy active metabolite of oxcarbazepine may be decreased. Monitor therapy

OxyCODONE: RifAMPin may decrease the serum concentration of OxyCODONE. Monitor therapy

Ozanimod: CYP2C8 Inducers (Moderate) may decrease serum concentrations of the active metabolite(s) of Ozanimod. CYP2C8 Inducers (Moderate) may decrease the serum concentration of Ozanimod. Avoid combination

Palbociclib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Palbociclib. Avoid combination

Paliperidone: Inducers of CYP3A4 (Strong) and P-glycoprotein may decrease the serum concentration of Paliperidone. Management: Monitor for reduced paliperidone effects when combined with strong inducers of both CYP3A4 and P-gp. Avoid use of these inducers with extended-release injectable paliperidone and instead manage patients with paliperidone extended-release tablets. Monitor therapy

Panobinostat: CYP3A4 Inducers (Strong) may decrease the serum concentration of Panobinostat. Avoid combination

PAZOPanib: CYP3A4 Inducers (Strong) may decrease the serum concentration of PAZOPanib. Avoid combination

Pemigatinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Pemigatinib. Avoid combination

Perampanel: CYP3A4 Inducers (Strong) may decrease the serum concentration of Perampanel. Management: Increase the perampanel starting dose to 4 mg/day when perampanel is used concurrently with moderate and strong CYP3A4 inducers. Monitor response to perampanel, particularly with changes to CYP3A4 inducer therapy. Consider therapy modification

Pexidartinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Pexidartinib. Avoid combination

Pimavanserin: CYP3A4 Inducers (Strong) may decrease the serum concentration of Pimavanserin. Avoid combination

Pioglitazone: CYP2C8 Inducers (Moderate) may decrease the serum concentration of Pioglitazone. Monitor therapy

Piperaquine: CYP3A4 Inducers (Strong) may decrease the serum concentration of Piperaquine. Avoid combination

Pitavastatin: Rifamycin Derivatives may increase the serum concentration of Pitavastatin. Management: Limit pitavastatin dose to a maximum of 2 mg/day with concurrent rifampin. Consider therapy modification

Pitolisant: CYP3A4 Inducers (Strong) may decrease the serum concentration of Pitolisant. Management: If on a stable pitolisant dose of 8.9 mg or 17.8 mg/day and starting a strong CYP3A4 inducer, double the pitolisant dose over 7 days (ie, to either 17.8 mg/day or 35.6 mg/day, respectively). Reduce pitolisant dose by 50% when the inducer is discontinued. Consider therapy modification

Polatuzumab Vedotin: CYP3A4 Inducers (Strong) may decrease the serum concentration of Polatuzumab Vedotin. Exposure to unconjugated MMAE, the cytotoxic small molecule component of polatuzumab vedotin, may be decreased. Monitor therapy

PONATinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of PONATinib. Avoid combination

Pralsetinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Pralsetinib. Management: Avoid concomitant use of pralsetinib with strong CYP3A4 inducers when possible. If combined, increase the starting dose of pralsetinib to double the current pralsetinib dosage starting on day 7 of coadministration. Consider therapy modification

Prasugrel: RifAMPin may diminish the antiplatelet effect of Prasugrel. Monitor therapy

Pravastatin: RifAMPin may decrease the serum concentration of Pravastatin. Monitor therapy

Praziquantel: CYP3A4 Inducers (Strong) may decrease the serum concentration of Praziquantel. Management: Use of praziquantel with strong CYP3A4 inducers is contraindicated. Discontinue rifampin 4 weeks prior to initiation of praziquantel therapy. Rifampin may be resumed the day following praziquantel completion. Avoid combination

PrednisoLONE (Systemic): CYP3A4 Inducers (Strong) may decrease the serum concentration of PrednisoLONE (Systemic). Monitor therapy

PredniSONE: CYP3A4 Inducers (Strong) may decrease the serum concentration of PredniSONE. Monitor therapy

Pretomanid: CYP3A4 Inducers (Strong) may decrease the serum concentration of Pretomanid. Avoid combination

Progestins (Contraceptive): Rifamycin Derivatives may decrease the serum concentration of Progestins (Contraceptive). Contraceptive failure is possible. Management: Contraceptive failure is possible. Use of an alternative, nonhormonal contraceptive is recommended. Recommendations outside the US recommend doubling the levonorgestrel dose to 3 mg if used for emergency contraception. Consider therapy modification

Propacetamol: RifAMPin may increase the metabolism of Propacetamol. . This may 1) diminish the desired effects of propacetamol; and 2) increase the risk of liver damage. Monitor therapy

Propafenone: CYP3A4 Inducers (Strong) may decrease the serum concentration of Propafenone. Monitor therapy

Propofol: RifAMPin may enhance the hypotensive effect of Propofol. Management: Avoid this combination if possible. Use of propofol in a patient who has been taking rifampin may result in clinically significant hypotension. Consider therapy modification

Prothionamide: RifAMPin may enhance the hepatotoxic effect of Prothionamide. Management: Avoid concomitant use of prothionamide and rifampin if possible. If combined use is considered necessary, monitor patients closely for signs and symptoms of hepatotoxicity (eg, jaundice, elevations in liver function tests). Consider therapy modification

Pyrazinamide: May enhance the hepatotoxic effect of RifAMPin. Severe (even fatal) liver injury has been reported in patients receiving these 2 drugs as a 2-month treatment regimen for latent TB infection. Management: Rifampin-pyrazinamide is generally not preferred for the treatment of latent tuberculosis (TB) due to the risk of hepatotoxicity. However, it is an option for patients at high risk of developing active TB who are unlikely to complete preferred treatment. Consider therapy modification

QUEtiapine: CYP3A4 Inducers (Strong) may decrease the serum concentration of QUEtiapine. Management: An increase in quetiapine dose (as much as 5 times the regular dose) may be required to maintain therapeutic benefit. Reduce the quetiapine dose back to the previous/regular dose within 7-14 days of discontinuing the inducer. Consider therapy modification

QuiNIDine: Rifamycin Derivatives may decrease the serum concentration of QuiNIDine. Management: Consider alternatives to combination treatment with quinidine and rifampin due to large potential decreases in quinidine concentrations. Monitor for decreased quinidine concentrations/effects with initiation/dose increase of any rifamycin derivative. Consider therapy modification

QuiNINE: RifAMPin may decrease the serum concentration of QuiNINE. Avoid combination

Radotinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Radotinib. Management: Consider alternatives to this combination when possible as the risk of radotinib treatment failure may be increased. Consider therapy modification

Raltegravir: RifAMPin may decrease the serum concentration of Raltegravir. Management: Increase raltegravir dose to 800 mg twice daily (adult dose) when used concomitantly with rifampin. Concurrent use of rifampin with once-daily raltegravir (Isentress HD) is not recommended. Consider therapy modification

Ramelteon: CYP3A4 Inducers (Strong) may decrease the serum concentration of Ramelteon. Monitor therapy

Ranolazine: CYP3A4 Inducers (Strong) may decrease the serum concentration of Ranolazine. Avoid combination

Reboxetine: CYP3A4 Inducers (Strong) may decrease the serum concentration of Reboxetine. Monitor therapy

Regorafenib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Regorafenib. Avoid combination

Remdesivir: CYP3A4 Inducers (Strong) may decrease the serum concentration of Remdesivir. Monitor therapy

Repaglinide: RifAMPin may decrease the serum concentration of Repaglinide. Monitor therapy

Revefenacin: OATP1B1/1B3 (SLCO1B1/1B3) Inhibitors may increase serum concentrations of the active metabolite(s) of Revefenacin. Avoid combination

Ribociclib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Ribociclib. Avoid combination

Rilpivirine: Rifamycin Derivatives may decrease the serum concentration of Rilpivirine. Avoid combination

Rimegepant: CYP3A4 Inducers (Strong) may decrease the serum concentration of Rimegepant. Avoid combination

Ripretinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Ripretinib. Avoid combination

RisperiDONE: CYP3A4 Inducers (Strong) may decrease the serum concentration of RisperiDONE. Management: Consider increasing the dose of oral risperidone (to no more than double the original dose) if a strong CYP3A4 inducer is initiated. For patients on IM risperidone, consider an increased IM dose or supplemental doses of oral risperidone. Consider therapy modification

Ritonavir: RifAMPin may decrease the serum concentration of Ritonavir. Avoid combination

Rivaroxaban: Inducers of CYP3A4 (Strong) and P-glycoprotein may decrease the serum concentration of Rivaroxaban. Avoid combination

Roflumilast: RifAMPin may decrease the serum concentration of Roflumilast. Management: Roflumilast U.S. prescribing information recommends against combining rifampin with roflumilast. The Canadian product monograph makes no such recommendation but notes that rifampin may reduce roflumilast therapeutic effects. Avoid combination

Rolapitant: CYP3A4 Inducers (Strong) may decrease the serum concentration of Rolapitant. Management: Avoid rolapitant use in patients requiring chronic administration of strong CYP3A4 inducers. Monitor for reduced rolapitant response and the need for alternative or additional antiemetic therapy even with shorter-term use of such inducers. Consider therapy modification

RomiDEPsin: RifAMPin may increase the serum concentration of RomiDEPsin. Avoid combination

Rosiglitazone: CYP2C8 Inducers (Moderate) may decrease the serum concentration of Rosiglitazone. Monitor therapy

Rosuvastatin: RifAMPin may decrease the serum concentration of Rosuvastatin. Monitor therapy

Ruxolitinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Ruxolitinib. Monitor therapy

Sacituzumab Govitecan: UGT1A1 Inducers may decrease serum concentrations of the active metabolite(s) of Sacituzumab Govitecan. Specifically, concentrations of SN-38 may be decreased. Avoid combination

Saquinavir: RifAMPin may enhance the adverse/toxic effect of Saquinavir. Specifically, the risk of hepatocellular toxicity may be increased. RifAMPin may decrease the serum concentration of Saquinavir. Avoid combination

SAXagliptin: CYP3A4 Inducers (Strong) may decrease the serum concentration of SAXagliptin. Monitor therapy

Selexipag: RifAMPin may decrease serum concentrations of the active metabolite(s) of Selexipag. Management: Increase the selexipag dose (up to 2-fold) when combined with rifampin. Monitor for decreased selexipag efficacy. Consider therapy modification

Selpercatinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Selpercatinib. Avoid combination

Selumetinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Selumetinib. Avoid combination

Sertraline: CYP3A4 Inducers (Strong) may decrease the serum concentration of Sertraline. Monitor therapy

Simeprevir: CYP3A4 Inducers (Strong) may decrease the serum concentration of Simeprevir. Avoid combination

Siponimod: RifAMPin may decrease the serum concentration of Siponimod. Avoid combination

Sirolimus: CYP3A4 Inducers (Strong) may decrease the serum concentration of Sirolimus. Management: Avoid concomitant use of strong CYP3A4 inducers and sirolimus if possible. If combined, monitor for reduced serum sirolimus concentrations. Sirolimus dose increases will likely be necessary to prevent subtherapeutic sirolimus levels. Consider therapy modification

Sodium Picosulfate: Antibiotics may diminish the therapeutic effect of Sodium Picosulfate. Management: Consider using an alternative product for bowel cleansing prior to a colonoscopy in patients who have recently used or are concurrently using an antibiotic. Consider therapy modification

Sofosbuvir: P-glycoprotein/ABCB1 Inducers may decrease the serum concentration of Sofosbuvir. Avoid combination

Sonidegib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Sonidegib. Avoid combination

SORAfenib: CYP3A4 Inducers (Strong) may decrease the serum concentration of SORAfenib. Avoid combination

SUFentanil: CYP3A4 Inducers (Strong) may decrease the serum concentration of SUFentanil. Monitor therapy

Sulfamethoxazole: RifAMPin may decrease the serum concentration of Sulfamethoxazole. Monitor therapy

Sulfonylureas: CYP2C9 Inducers (Moderate) may decrease the serum concentration of Sulfonylureas. Monitor therapy

SUNItinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of SUNItinib. Management: Avoid when possible. If combined, increase sunitinib dose to a max of 87.5 mg daily when treating GIST or RCC. Increase sunitinib dose to a max of 62.5 mg daily when treating PNET. Monitor patients for both reduced efficacy and increased toxicities. Consider therapy modification

Tacrolimus (Systemic): CYP3A4 Inducers (Strong) may decrease the serum concentration of Tacrolimus (Systemic). Management: Monitor for decreased tacrolimus concentrations and effects when combined with strong CYP3A4 inducers. Tacrolimus dose increases will likely be needed during concomitant use. Consider therapy modification

Tadalafil: CYP3A4 Inducers (Strong) may decrease the serum concentration of Tadalafil. Management: Erectile dysfunction or BPH: monitor for decreased effectiveness - no standard dose adjustments recommended. Avoid use of tadalafil for pulmonary arterial hypertension in patients receiving a strong CYP3A4 inducer. Consider therapy modification

Tamoxifen: Rifamycin Derivatives may increase the metabolism of Tamoxifen. Management: Consider alternatives to coadministration of rifampin and tamoxifen. If this combination cannot be avoided, monitor for decrease tamoxifen efficacy. It is unclear if rifapentine or rifabutin would participate in this interaction. Consider therapy modification

Tamoxifen: CYP3A4 Inducers (Strong) may decrease serum concentrations of the active metabolite(s) of Tamoxifen. CYP3A4 Inducers (Strong) may decrease the serum concentration of Tamoxifen. Management: Consider alternatives to concomitant use of strong CYP3A4 inducers and tamoxifen. If the combination cannot be avoided, monitor for reduced therapeutic effects of tamoxifen. Consider therapy modification

Tasimelteon: CYP3A4 Inducers (Strong) may decrease the serum concentration of Tasimelteon. Avoid combination

Tazemetostat: CYP3A4 Inducers (Strong) may decrease the serum concentration of Tazemetostat. Avoid combination

Telithromycin: CYP3A4 Inducers (Strong) may decrease the serum concentration of Telithromycin. Avoid combination

Temsirolimus: Rifamycin Derivatives may decrease the serum concentration of Temsirolimus. Rifamycins will likely cause an even greater decrease in the concentration of the active metabolite sirolimus. Management: Temsirolimus prescribing information recommends against coadministration with strong CYP3A4 inducers such as rifampin; however, if concurrent therapy is necessary, an increase in temsirolimus adult dose to 50 mg/week should be considered. Consider therapy modification

Temsirolimus: CYP3A4 Inducers (Strong) may decrease the serum concentration of Temsirolimus. Management: Avoid concomitant use of temsirolimus and strong CYP3A4 inducers. If coadministration is unavoidable, increase temsirolimus dose to 50 mg per week. Resume previous temsirolimus dose after discontinuation of the strong CYP3A4 inducer. Consider therapy modification

Tenofovir Alafenamide: RifAMPin may decrease the serum concentration of Tenofovir Alafenamide. Avoid combination

Terbinafine (Systemic): RifAMPin may decrease the serum concentration of Terbinafine (Systemic). Monitor therapy

Teriflunomide: May increase the serum concentration of OATP1B1/1B3 (SLCO1B1/1B3) Substrates. Monitor therapy

Tertatolol: RifAMPin may decrease the serum concentration of Tertatolol. Monitor therapy

Tetrahydrocannabinol: CYP3A4 Inducers (Strong) may decrease the serum concentration of Tetrahydrocannabinol. Monitor therapy

Tetrahydrocannabinol and Cannabidiol: CYP3A4 Inducers (Strong) may decrease the serum concentration of Tetrahydrocannabinol and Cannabidiol. Monitor therapy

Tezacaftor and Ivacaftor: CYP3A4 Inducers (Strong) may decrease the serum concentration of Tezacaftor and Ivacaftor. Avoid combination

Thiotepa: CYP3A4 Inducers (Strong) may increase serum concentrations of the active metabolite(s) of Thiotepa. CYP3A4 Inducers (Strong) may decrease the serum concentration of Thiotepa. Management: Thiotepa prescribing information recommends avoiding concomitant use of thiotepa and strong CYP3A4 inducers. If concomitant use is unavoidable, monitor for adverse effects. Consider therapy modification

Thyroid Products: RifAMPin may decrease the serum concentration of Thyroid Products. Monitor therapy

TiaGABine: CYP3A4 Inducers (Strong) may decrease the serum concentration of TiaGABine. Management: Approximately 2-fold higher tiagabine doses and a more rapid dose titration will likely be required in patients concomitantly taking a strong CYP3A4 inducer. Consider therapy modification

Ticagrelor: CYP3A4 Inducers (Strong) may decrease serum concentrations of the active metabolite(s) of Ticagrelor. CYP3A4 Inducers (Strong) may decrease the serum concentration of Ticagrelor. Avoid combination

Tipranavir: RifAMPin may decrease the serum concentration of Tipranavir. Avoid combination

Tofacitinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Tofacitinib. Avoid combination

Tolvaptan: CYP3A4 Inducers (Strong) may decrease the serum concentration of Tolvaptan. Management: Avoid concurrent use of strong CYP3A4 inducers with the Jynarque brand of tolvaptan. For patients receiving the Samsca brand of tolvaptan, monitor patient response to tolvaptan and adjust tolvaptan dose if required. Consider therapy modification

Toremifene: CYP3A4 Inducers (Strong) may decrease serum concentrations of the active metabolite(s) of Toremifene. CYP3A4 Inducers (Strong) may decrease the serum concentration of Toremifene. Avoid combination

Torsemide: CYP2C9 Inducers (Moderate) may decrease the serum concentration of Torsemide. Monitor therapy

Trabectedin: CYP3A4 Inducers (Strong) may decrease the serum concentration of Trabectedin. Avoid combination

TraMADol: CYP3A4 Inducers (Strong) may decrease the serum concentration of TraMADol. Monitor therapy

Triamcinolone (Systemic): CYP3A4 Inducers (Strong) may decrease the serum concentration of Triamcinolone (Systemic). Monitor therapy

Trimethoprim: RifAMPin may decrease the serum concentration of Trimethoprim. Monitor therapy

Tropisetron: CYP3A4 Inducers (Strong) may decrease the serum concentration of Tropisetron. Monitor therapy

Tucatinib: CYP2C8 Inducers (Moderate) may decrease the serum concentration of Tucatinib. Avoid combination

Typhoid Vaccine: Antibiotics may diminish the therapeutic effect of Typhoid Vaccine. Only the live attenuated Ty21a strain is affected. Management: Avoid use of live attenuated typhoid vaccine (Ty21a) in patients being treated with systemic antibacterial agents. Postpone vaccination until 3 days after cessation of antibiotics and avoid starting antibiotics within 3 days of last vaccine dose. Consider therapy modification

Ubrogepant: CYP3A4 Inducers (Strong) may decrease the serum concentration of Ubrogepant. Avoid combination

Udenafil: CYP3A4 Inducers (Strong) may decrease the serum concentration of Udenafil. Monitor therapy

Ulipristal: CYP3A4 Inducers (Strong) may decrease the serum concentration of Ulipristal. Avoid combination

Upadacitinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Upadacitinib. Avoid combination

Valbenazine: CYP3A4 Inducers (Strong) may decrease serum concentrations of the active metabolite(s) of Valbenazine. CYP3A4 Inducers (Strong) may decrease the serum concentration of Valbenazine. Avoid combination

Valproate Products: RifAMPin may decrease the serum concentration of Valproate Products. Management: Doses of valproate products may require adjustment when starting or stopping concurrent rifampin. Monitor plasma valproate concentrations closely and monitor for possible changes in clinical response. Consider therapy modification

Vandetanib: CYP3A4 Inducers (Strong) may increase serum concentrations of the active metabolite(s) of Vandetanib. CYP3A4 Inducers (Strong) may decrease the serum concentration of Vandetanib. Avoid combination

Velpatasvir: CYP2B6 Inducers (Moderate) may decrease the serum concentration of Velpatasvir. Avoid combination

Velpatasvir: CYP3A4 Inducers (Strong) may decrease the serum concentration of Velpatasvir. Avoid combination

Vemurafenib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Vemurafenib. Management: Avoid coadministration of vemurafenib and strong CYP3A4 inducers if possible. If coadministration is unavoidable, increase the vemurafenib dose by 240 mg as tolerated. Resume prior vemurafenib dose 2 weeks after discontinuation of strong CYP3A4 inducer. Consider therapy modification

Venetoclax: CYP3A4 Inducers (Strong) may decrease the serum concentration of Venetoclax. Avoid combination

Verapamil: CYP3A4 Inducers (Strong) may decrease the serum concentration of Verapamil. Management: Consider alternatives to this combination. If combined, monitor for reduced verapamil efficacy. Verapamil dose increases may be necessary. Consider therapy modification

Vilazodone: CYP3A4 Inducers (Strong) may decrease the serum concentration of Vilazodone. Management: Consider increasing vilazodone dose by as much as 2-fold (do not exceed 80 mg/day), based on response, in patients receiving strong CYP3A4 inducers for > 14 days. Reduce to the original vilazodone dose over 1 to 2 weeks after inducer discontinuation. Consider therapy modification

VinCRIStine (Liposomal): CYP3A4 Inducers (Strong) may decrease the serum concentration of VinCRIStine (Liposomal). Avoid combination

VinCRIStine (Liposomal): P-glycoprotein/ABCB1 Inducers may decrease the serum concentration of VinCRIStine (Liposomal). Avoid combination

Vinflunine: CYP3A4 Inducers (Strong) may decrease the serum concentration of Vinflunine. Avoid combination

Vitamin K Antagonists (eg, warfarin): Rifamycin Derivatives may decrease the serum concentration of Vitamin K Antagonists. Management: Monitor for reduced anticoagulant effects (ie, decreased INR, thromboembolic events) if a rifamycin derivative is initiated in a vitamin K antagonist treated patient. Vitamin K antagonist dose adjustments will likely be required. Consider therapy modification

Vorapaxar: CYP3A4 Inducers (Strong) may decrease the serum concentration of Vorapaxar. Avoid combination

Voriconazole: RifAMPin may decrease the serum concentration of Voriconazole. Avoid combination

Vortioxetine: CYP3A4 Inducers (Strong) may decrease the serum concentration of Vortioxetine. Management: Consider increasing the vortioxetine dose to no more than 3 times the original dose when used with a strong drug metabolism inducer for more than 14 days. The vortioxetine dose should be returned to normal within 14 days of stopping the strong inducer. Consider therapy modification

Voxelotor: CYP3A4 Inducers (Strong) may decrease the serum concentration of Voxelotor. Management: Avoid concomitant use of voxelotor and strong CYP3A4 inducers. If concomitant use is unavoidable, increase the voxelotor dose to 2,500 mg once daily. Consider therapy modification

Voxilaprevir: RifAMPin may increase the serum concentration of Voxilaprevir. Specifically, a single dose of rifampin may increase voxilaprevir concentrations, while chronic daily use of rifampin may decrease voxilaprevir concentrations. RifAMPin may decrease the serum concentration of Voxilaprevir. Avoid combination

Zaleplon: CYP3A4 Inducers (Strong) may decrease the serum concentration of Zaleplon. Management: Consider the use of an alternative hypnotic that is not metabolized by CYP3A4 in patients receiving strong CYP3A4 inducers. If zaleplon is combined with a strong CYP3A4 inducer, monitor for decreased effectiveness of zaleplon. Consider therapy modification

Zanubrutinib: CYP3A4 Inducers (Strong) may decrease the serum concentration of Zanubrutinib. Avoid combination

Zidovudine: Rifamycin Derivatives may decrease the serum concentration of Zidovudine. Monitor therapy

Zolpidem: RifAMPin may decrease the serum concentration of Zolpidem. Avoid combination

Zonisamide: CYP3A4 Inducers (Strong) may decrease the serum concentration of Zonisamide. Monitor therapy

Zopiclone: CYP3A4 Inducers (Strong) may decrease the serum concentration of Zopiclone. Monitor therapy

Zuclopenthixol: CYP3A4 Inducers (Strong) may decrease the serum concentration of Zuclopenthixol. Monitor therapy

Test Interactions

May interfere with urine detection of opioids (false-positive); positive Coombs' reaction [direct], rifampin inhibits standard assay's ability to measure serum folate and B12; transient increase in LFTs and decreased biliary excretion of contrast media

Adverse Reactions

The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified.

Frequency not defined:

Cardiovascular: Decreased blood pressure, flushing, shock, vasculitis

Central nervous system: Ataxia, behavioral changes, confusion, dizziness, drowsiness, fatigue, headache, lack of concentration, myasthenia, numbness, peripheral pain, sore mouth

Dermatologic: Erythema multiforme, pemphigoid reaction, pruritus, skin rash, urticaria

Endocrine & metabolic: Adrenocortical insufficiency, menstrual disease

Gastrointestinal: Abdominal cramps, anorexia, diarrhea, epigastric discomfort, flatulence, glossalgia, heartburn, nausea, staining of tooth, vomiting

Genitourinary: Hemoglobinuria, hematuria

Hematologic & oncologic: Decreased hemoglobin, disorder of hemostatic components of blood (vitamin K-dependent), disseminated intravascular coagulation, eosinophilia, hemolysis, hemolytic anemia, hemorrhage, leukopenia, thrombocytopenia (especially with high-dose therapy)

Hepatic: Abnormal hepatic function tests, hepatic insufficiency, hyperbilirubinemia, jaundice

Hypersensitivity: Hypersensitivity reaction

Neuromuscular & skeletal: Myopathy

Ophthalmic: Conjunctivitis, visual disturbance

Renal: Acute renal failure, interstitial nephritis, renal insufficiency, renal tubular necrosis

Respiratory: Dyspnea, flu-like symptoms, wheezing

Miscellaneous: Fever

<1%, postmarketing, and/or case reports: Acute generalized exanthematous pustulosis, agranulocytosis, anaphylaxis, cerebral hemorrhage, cholestasis, Clostridioides difficile colitis, cutaneous lupus erythematosus (Patel 2001), drug reaction with eosinophilia and systemic symptoms, facial edema, hepatitis (including shock-like syndrome with hepatic involvement), increased blood urea nitrogen, increased uric acid, peripheral edema, psychosis, severe dermatological reaction, Stevens-Johnson syndrome, toxic epidermal necrolysis

Warnings/Precautions

Concerns related to adverse effects:

• Coagulopathy: May cause vitamin K-dependent coagulation disorders and bleeding. Monitor coagulation tests during treatment in patients at risk of vitamin K deficiency (eg, chronic liver disease, poor nutritional status, prolonged use of antibacterial agents or anticoagulants). Consider discontinuation if abnormal coagulation tests and/or bleeding occurs; consider supplemental vitamin K administration when appropriate.

• Dermatologic reactions: Cases of severe cutaneous adverse reactions (SCAR) such as Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), acute generalized exanthematous pustulosis (AGEP), and drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome have been reported. Discontinue treatment immediately and institute appropriate therapy if signs or symptoms of SCAR develop.

• Flu-like syndrome: Regimens of >600 mg once or twice weekly in adults have been associated with a high incidence of adverse reactions including a flu-like syndrome.

• Hematologic effects: May cause thrombocytopenia, leukopenia, or anemia with regimens >600 mg once or twice weekly in adults.

• Hepatotoxicity: Hepatotoxicity of hepatocellular, cholestatic, and mixed patterns has been reported; may include asymptomatic elevations in liver enzymes, isolated jaundice/hyperbilirubinemia, symptomatic self-limited hepatitis, or fulminant liver failure and death. Severe reactions, including fatalities, have occurred in patients with preexisting hepatic failure and in patients receiving concomitant hepatotoxic agents. Monitor for signs and symptoms of liver injury, especially if treatment is prolonged or given with other hepatotoxic drugs. Patients with impaired liver function should only be given rifampin when medically indicated and with monitoring of LFTs (AST, ALT, bilirubin) prior to therapy and then every 2 to 4 weeks during therapy. Discontinue use if hepatocellular damage occurs or worsens.

• Hypersensitivity: Hypersensitivity reactions have been reported. Signs and symptoms of hypersensitivity reactions may include fever, rash, urticaria, angioedema, hypotension, acute bronchospasm, conjunctivitis, thrombocytopenia, neutropenia, elevated liver transaminases, or flu-like syndrome. Monitor patients for signs/symptoms of hypersensitivity; discontinue therapy if signs/symptoms suggestive of hypersensitivity (eg, fever, lymphadenopathy, eosinophilia, liver abnormalities) occur, even if rash is not evident.

• Superinfection: Prolonged use may result in fungal or bacterial superinfection, including C. difficile-associated diarrhea (CDAD) and pseudomembranous colitis; CDAD has been observed >2 months postantibiotic treatment.

Disease-related concerns:

• Alcoholism: Use with caution in patients with a history of alcoholism (even if ethanol consumption is discontinued during therapy).

• Diabetes mellitus: Use with caution in patients with diabetes mellitus; management of diabetes may be more difficult in patients taking rifampin.

• Hepatic impairment: Use with caution and close monitoring in patients with hepatic impairment.

• Meningococcal disease: Do not use for treatment of meningococcal disease, only for short-term treatment of asymptomatic carrier states.

• Porphyria: Use with caution in patients with porphyria; exacerbations have been reported due to enzyme-inducing properties.

Other warnings/precautions:

• Appropriate administration: Do not administer IV form via IM or SubQ routes; restart infusion at another site if extravasation occurs.

• Compliance: Monitor for compliance in patients on intermittent therapy.

• Contact lenses: Remove soft contact lenses during therapy since permanent staining may occur.

• Discoloration: Teeth (may be permanent), urine, feces, saliva, sweat, and tears may be discolored (yellow, orange, red, or brown).

Monitoring Parameters

Baseline LFTs (AST, ALT, bilirubin), serum creatinine, CBC; periodic (every 2 to 4 weeks during therapy) monitoring of liver function in patients with preexisting hepatic impairment and periodic monitoring of serum creatinine and CBC in patients with baseline abnormalities. Mental status, sputum culture, chest X-ray 2 to 3 months into treatment. Monitor coagulation tests during treatment in patients at risk of vitamin K deficiency.

Reproductive Considerations

Rifampin may decrease the effectiveness of hormonal contraceptives. Consult drug interactions database for more detailed information specific to use of rifampin and specific contraceptives.

Pregnancy Considerations

Rifampin crosses the human placenta. Postnatal hemorrhages have been reported in the infant and mother with administration during the last few weeks of pregnancy.

Rifampin is approved for the treatment of tuberculosis. Active tuberculosis infection is associated with adverse fetal outcomes, including intrauterine growth restriction, low birth weight, preterm birth, and perinatal death (Esmail 2018; Miele 2020), as well as adverse maternal outcomes, including increased risks for anemia and cesarean delivery. Placental transmission may rarely occur with active maternal disease (Miele 2020). Due to the risks of untreated tuberculosis, rifampin is recommended as part of the initial treatment regimen of drug-susceptible active tuberculosis when the probability of maternal disease is moderate to high (ATS/CDC/IDSA [Nahid 2016]). Rifampin may also be considered for the treatment of latent tuberculosis infection (also known as prophylaxis or preventive therapy) in pregnant patients (WHO 2020). Rifampin may be associated with an increased risk of maternal hepatotoxicity, which may require temporary drug withdrawal in pregnant and postpartum patients (Beck-Friis 2020).

Rifampin is used off-label for the treatment of brucellosis infection. Brucellosis infection may increase the risk of spontaneous abortion; rifampin is recommended for the treatment of brucellosis infection during pregnancy (CDC 2017).

Rifampin may be considered for use as an alternative agent in pregnant patients for the treatment of mild illness due to human anaplasmosis (also known as human granulocytic anaplasmosis); case reports have shown favorable maternal and pregnancy outcomes in small numbers of rifampin-treated pregnant women (CDC [Biggs 2016]).

Patient Education

What is this drug used for?

• It is used to treat TB (tuberculosis).

• It is used to stop the spread of meningitis in people who carry the bacteria but are not sick with the disease.

• It may be given to you for other reasons. Talk with the doctor.

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Diarrhea

• Fatigue

• Passing gas

• Headache

• Nausea

• Vomiting

• Lack of appetite

• Heartburn

• Abdominal cramps

• Body fluid discoloration

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• High blood sugar like confusion, fatigue, increased thirst, increased hunger, passing a lot of urine, flushing, fast breathing, or breath that smells like fruit

• Kidney problems like unable to pass urine, blood in the urine, change in amount of urine passed, or weight gain

• Liver problems like dark urine, fatigue, lack of appetite, nausea, abdominal pain, light-colored stools, vomiting, or yellow skin or eyes

• Severe loss of strength and energy

• Confusion

• Dizziness

• Passing out

• Flu-like symptoms

• Chills

• Sore throat

• Swollen glands

• Joint pain

• Joint swelling

• Muscle pain

• Muscle weakness

• Shortness of breath

• Chest pain

• Cough

• Sweating a lot

• Abnormal heartbeat

• Swelling of arms or legs

• Bruising

• Bleeding

• Pinpoint red spots on skin

• Change in balance

• Trouble focusing

• Behavioral changes

• Menstrual changes

• Vision changes

• Eye pain

• Severe eye irritation

• Severe injection site redness, burning, pain, swelling, or fluid leakage

• Stevens-Johnson syndrome/toxic epidermal necrolysis like red, swollen, blistered, or peeling skin (with or without fever); red or irritated eyes; or sores in mouth, throat, nose, or eyes

• Tooth discoloration

Clostridioides (formerly Clostridium) difficile-associated diarrhea like abdominal pain or cramps, severe diarrhea or watery stools, or bloody stools

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.

Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.

Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a limited summary of general information about the medicine’s uses from the patient education leaflet and is not intended to be comprehensive. This limited summary does NOT include all information available about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not intended to provide medical advice, diagnosis or treatment and does not replace information you receive from the healthcare provider. For a more detailed summary of information about the risks and benefits of using this medicine, please speak with your healthcare provider and review the entire patient education leaflet.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Frequently Asked Questions