Penicillin V Potassium
Medically reviewed by Drugs.com. Last updated on Jul 22, 2020.
(pen i SIL in vee poe TASS ee um)
- Pen VK
- Phenoxymethyl Penicillin
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Solution Reconstituted, Oral:
Generic: 125 mg/5 mL (100 mL, 200 mL); 250 mg/5 mL (100 mL, 200 mL)
Generic: 250 mg, 500 mg
- Antibiotic, Penicillin
Inhibits bacterial cell wall synthesis by binding to one or more of the penicillin-binding proteins (PBPs); which in turn inhibits the final transpeptidation step of peptidoglycan synthesis in bacterial cell walls, thus inhibiting cell wall biosynthesis. Bacteria eventually lyse due to ongoing activity of cell wall autolytic enzymes (autolysins and murein hydrolases) while cell wall assembly is arrested.
Urine (as unchanged drug and metabolites)
<2 hours (Heikkilä 1993; Lindberg 1987).
Special Populations: Renal Function Impairment
Excretion is considerably delayed.
Special Populations: Children
In neonates and young infants, excretion is considerably delayed.
Use: Labeled Indications
Erysipelas: Treatment of mild infection or step-down therapy after initial parenteral therapy.
Odontogenic infection (acute simple gingivitis): Treatment of odontogenic infection, in conjunction with dental care for infections involving gum tissue.
Pneumococcal infections: Treatment of mild to moderately severe pneumococcal respiratory tract infections, including otitis media.
Streptococcus (group A): Secondary prophylaxis for rheumatic fever (prevention of secondary attacks).
Streptococcus (group A) pharyngitis: Initial treatment of pharyngitis caused by group A Streptococcus.
Off Label Uses
Data from a limited number of patients studied suggest that penicillin V potassium may be beneficial for the treatment of actinomycosis after initial surgical intervention and IV therapy with penicillin G (if clinically indicated) [Hsieh 1993], [Sudhakar 2004]. Clinical experience also suggests the utility of penicillin V potassium in the treatment of actinomycosis [Brook 2020], [Smego 1998].
Based on the Centers for Disease Control and Prevention (CDC) expert panel meetings on prevention and treatment of anthrax in adults, penicillin V potassium is an effective and acceptable alternative for postexposure prophylaxis and for treatment of cutaneous anthrax (without systemic involvement) for penicillin-susceptible strains [CDC [Hendricks 2014]].
In addition, the Infectious Diseases Society of America (IDSA) practice guidelines for the diagnosis and management of skin and soft tissue infections (SSTIs) state that penicillin V potassium is effective and recommended for the treatment of cutaneous anthrax (community acquired) [IDSA [Stevens 2014]].
Asplenia, prophylaxis against bacterial infection in select high-risk patients
Clinical experience suggests the utility of penicillin V potassium to prevent bacterial infections in high-risk patients with functional or anatomic asplenia [Pasternack 2020], [Spelman 2008].
Bite wound infection, prophylaxis of high-risk bite or treatment (animal or human bite)
Based on the IDSA practice guidelines for the diagnosis and management of SSTIs, penicillin V potassium, as part of an appropriate combination regimen, is an effective and recommended option for prophylaxis or treatment of animal bites [IDSA [Stevens 2014]]. Clinical experience also suggests the utility of penicillin V potassium for prophylaxis or treatment of animal or human bites [Baddour 2020a], [Baddour 2020b].
Diphtheria (adjunctive therapy with antitoxin)
Based on the CDC’s Epidemiology and Prevention of Vaccine-Preventable Diseases (the “Pink Book”), penicillin V potassium is effective and recommended as oral step-down therapy following parenteral treatment for the management of diphtheria [CDC 2015].
Erysipeloid (localized cutaneous Erysipelothrix rhusiopathiae infection)
Based on the IDSA practice guidelines for the diagnosis and management of SSTIs, penicillin V potassium is effective and recommended for the treatment of cutaneous erysipeloid [IDSA [Stevens 2014]].
Meningococcal prophylaxis in patients with complement deficiency (eg, due to C5 inhibitor therapy)
Clinical experience suggests the utility of penicillin V potassium in the prevention of meningococcal infection for patients with complement deficiency, including patients receiving C5 inhibitors [Apicella 2020], [Hawkins 2017], [Liszewski 2020], [McNamara 2017].
Nonpurulent cellulitis, long-term chronic suppression
Based on the IDSA practice guidelines for the diagnosis and management of SSTIs, penicillin V potassium is effective and recommended for the prevention of recurrent nonpurulent beta-hemolytic streptococcal cellulitis in patients with 3 or more episodes per year [IDSA [Stevens 2014]].
Pneumococcal prophylaxis in allogeneic hematopoietic cell transplant
Based on the American Society for Blood and Marrow Transplantation guidelines for preventing infectious complications among hematopoietic cell transplant (HCT) recipients, penicillin V potassium may be used in HCT recipients with chronic graft-vs-host disease or low IgG levels to prevent invasive pneumococcal infection in areas where the incidence of penicillin-resistant Streptococcus pneumoniae is low [ASBMT [Tomblyn 2009]].
Prosthetic joint infection, chronic suppression
Based on the IDSA clinical practice guideline for the diagnosis and management of prosthetic joint infection (PJI), penicillin V potassium is an effective and recommended agent for chronic antimicrobial suppression of PJI with beta-hemolytic streptococci, Enterococcus spp. (penicillin susceptible), or Cutibacterium spp. after completion of parenteral therapy [IDSA [Osmon 2013]].
Rat bite fever, uncomplicated infection
Clinical experience suggests the utility of penicillin V potassium in the treatment of uncomplicated rat bite fever [King 2020], [Washburn 2015].
Streptococcus (group A) chronic carriage
Based on the IDSA clinical practice guideline for the diagnosis and management of group A streptococcal pharyngitis, penicillin V potassium is effective and recommended for the management of group A streptococcal pharyngitis in chronic carriers of group A streptococci [IDSA [Shulman 2012]].
Hypersensitivity to penicillin or any component of the formulation
Actinomycosis (off-label use):
Note: For initial therapy of mild infection or step-down therapy following parenteral treatment of severe infection.
Oral: 500 mg to 1 g every 6 hours (Brook 2020; Hsieh 1993; Smego 1998). Optimal duration is uncertain; some experts suggest total durations of 2 to 6 months for mild infection and 6 to 12 months for severe or extensive infection (Brook 2020).
Anthrax (alternative agent for penicillin-susceptible strains) (off-label use):
Note: Consult public health officials for event-specific recommendations. A high index of suspicion for emergent beta-lactam resistance during therapy is warranted (CDC [Hendricks 2014]).
Inhalational exposure (postexposure prophylaxis): Oral: 500 mg every 6 hours (CDC [Hendricks 2014]); duration depends on anthrax vaccine status and series completion, age, immune status, and pregnancy/breastfeeding status; for those who have not previously received anthrax vaccine, duration ranges from 42 to 60 days (CDC [Bower 2019). Note: Anthrax vaccine should also be administered to exposed individuals (CDC [Bower 2019]; CDC [Hendricks 2014]).
Cutaneous, without systemic involvement, treatment: Oral: 500 mg every 6 hours; duration is 7 to 10 days after naturally acquired infection and 60 days following biological weapon–related event. Note: Patients with extensive edema or cutaneous lesions of the head or neck should be treated with a parenteral regimen recommended for systemic infection (CDC [Hendricks 2014]).
Asplenia, prophylaxis against bacterial infection in select high-risk patients (off-label use):
Oral: 250 mg twice daily. Duration varies based on patient-specific factors (Pasternack 2020; Spelman 2008).
Bite wound infection, prophylaxis of high-risk bite or treatment (animal or human bite) (alternative agent) (off-label use):
Oral: 500 mg 4 times daily as part of an appropriate combination regimen. For prophylaxis, duration is 3 to 5 days; for treatment of established infection, duration is typically 5 to 14 days and varies based on clinical response and patient-specific factors (Baddour 2020a; Baddour 2020b; IDSA [Stevens 2014]).
Diphtheria (adjunctive therapy with antitoxin) (off-label use):
Oral: 250 mg 4 times daily following parenteral treatment, to complete a total treatment course of 14 days (CDC 2015).
Meningococcal prophylaxis in patients with complement deficiency (eg, due to C5 inhibitor therapy) (off-label use): Limited data:
Oral: 500 mg twice daily in addition to meningococcal vaccination; for those taking a C5 inhibitor, administer meningococcal vaccination 2 weeks prior to initiation of C5 inhibitor therapy and give penicillin V potassium for the duration of C5 inhibitor therapy (Apicella 2020; Hawkins 2017; Liszewski 2020; McNamara 2017).
Odontogenic infection: Acute simple gingivitis:
Note: Reserve therapy for patients with rapidly progressive disease, severe pain, or immunocompromising conditions (Chow 2020).
Oral: 500 mg every 6 to 8 hours for 5 to 7 days in combination with metronidazole (Chow 2020; manufacturer's labeling).
Pneumococcal prophylaxis in allogeneic hematopoietic cell transplant (off-label use):
Note: For select patients post-engraftment (eg, those with chronic graft-vs-host disease or hypogammaglobulinemia); use only in areas where incidence of penicillin-resistant Streptococcus pneumoniae is low.
Oral: 250 to 500 mg twice daily (ASBMT [Tomblyn 2009]).
Prosthetic joint infection, chronic suppression (off-label use):
Note: For infection caused by beta-hemolytic streptococci, penicillin-susceptible Enterococcus spp., or Cutibacterium spp. (following pathogen-specific IV therapy in patients undergoing 1-stage exchange or debridement with retention of prosthesis) (Berbari 2020; IDSA [Osmon 2013]).
Oral: 500 mg 2 to 4 times daily (IDSA [Osmon 2013]); duration depends on patient-specific factors (Berbari 2020).
Rat bite fever, uncomplicated infection (off-label use):
Oral: 500 mg every 6 hours following parenteral therapy to complete a total treatment course of 14 days (King 2020; Washburn 2015).
Skin and soft tissue infection:
Erysipelas, treatment of mild infection or step-down therapy after initial parenteral therapy: Oral: 500 mg every 6 hours; total duration is 5 days, with extension to 14 days for slow response, severe infection, or immunosuppression (IDSA [Stevens 2014]; Spelman 2020).
Erysipeloid (localized cutaneous Erysipelothrix rhusiopathiae infection), treatment (off-label use): Oral: 500 mg every 6 hours for 5 to 10 days (IDSA [Stevens 2014]; Reboli 2020).
Nonpurulent cellulitis, long-term suppression (secondary prophylaxis) (off-label use): Note: For patients with ≥3 episodes/year of beta-hemolytic streptococcal cellulitis when predisposing factors cannot be controlled (IDSA [Stevens 2014]).
Oral: 250 to 500 mg twice daily after completion of treatment (IDSA [Stevens 2014]; Spelman 2020; Thomas 2013).
Streptococcus (group A):
Pharyngitis: Oral: 500 mg 2 to 3 times daily for 10 days (AHA [Gerber 2009]; IDSA [Shulman 2012]).
Secondary prophylaxis for rheumatic fever (prevention of recurrent attacks) (alternative agent): Oral: 250 mg twice daily. Duration depends on risk factors, age, and presence of valvular disease (AHA [Gerber 2009]).
Chronic carriage (off-label use): Note: Most individuals with chronic carriage do not require antimicrobial treatment (IDSA [Shulman 2012]).
Oral: 500 mg 4 times daily for 10 days; add rifampin for the last 4 days of therapy (Chaudhary 1985; IDSA [Shulman 2012]).
Refer to adult dosing.
General dosing: Infants, Children, and Adolescents:
Mild to moderate infection: Oral: 25 to 50 mg/kg/day in divided doses every 6 hours; maximum daily dose: 2,000 mg/day (Bradley 2019; Red Book [AAP 2018]).
Anthrax (penicillin-susceptible strains) (alternative agent) (AAP [Bradley 2014]): Infants, Children, and Adolescents:
Postexposure prophylaxis, exposure to aerosolized spores: Oral: 50 to 75 mg/kg/day in divided doses every 6 to 8 hours for 60 days.
Cutaneous, without systemic involvement: Oral: 50 to 75 mg/kg/day in divided doses every 6 to 8 hours. Duration: 7 to 10 days for naturally acquired infection, up to 60 days for biological weapon-related event/exposure to aerosolized spore.
Systemic, oral step-down therapy: Oral: 50 to 75 mg/kg/day in divided doses every 6 to 8 hours to complete 60-day course; should be used as a component of combination therapy.
Fusospirochetosis (Vincent infection), mild to moderately severe infections: Children ≥12 years and Adolescents: Oral: 250 to 500 mg every 6 to 8 hours.
Group A streptococcal infection:
Pharyngitis, acute treatment (primary prevention of rheumatic fever) (AHA [Gerber 2009]; IDSA [Shulman 2012]; Red Book [AAP 2018]; WHO 2004):
Children <27 kg: Oral: 250 mg 2 to 3 times daily for 10 days.
Children ≥27 kg and Adolescents: Oral: 500 mg 2 to 3 times daily for 10 days; in adolescents, 250 mg 4 times daily has also been suggested.
Rheumatic fever, secondary prevention: Children and Adolescents: Oral: 250 mg twice daily (AHA [Gerber 2009]).
Chronic carriers of Group A Streptococcus, treatment: Note: Antibiotic therapy is generally not recommended for chronic Streptococcus pyogenes carriage; however, it may be considered in certain cases (IDSA [Shulman 2012]; Red Book [AAP 2018]).
Children and Adolescents: Oral: 50 mg/kg/day in 4 divided doses for 10 days in combination with oral rifampin for the last 4 days; maximum daily dose: 2,000 mg/day (IDSA [Shulman 2012]).
Pneumonia, community-acquired; Group A Streptococcus, mild infection or step-down therapy:
Infants, Children, and Adolescents: Oral: 50 to 75 mg/kg/day in divided doses 4 times daily (Bradley 2019; Red Book [AAP 2018]); Note: Usual adult maximum daily dose is 2,000 mg/day.
Pneumococcal infection prophylaxis, anatomic or functional asplenia (eg, sickle cell disease [SCD]) (AAP 2000; Gaston 1986; NHLBI 2014):
Infants (as soon as SCD diagnosed or asplenic) and Children <3 years: Oral: 125 mg twice daily.
Children ≥3 years: Oral: 250 mg twice daily.
Note: Current guidelines recommend discontinuation of prophylaxis at 5 years of age unless the patient has experienced invasive pneumococcal infection or splenectomy; data regarding when to discontinue are limited and practice varies; decision should be made on a case-by-case basis (McCavit 2013; Red Book [AAP 2018]).
Pneumococcal infection prophylaxis, patients post-hematopoietic cell transplant with chronic graft-versus-host disease or low IgG levels (Tomblyn 2009): Note: Use only in areas where incidence of penicillin-resistant Streptococcus pneumoniae is low.
Infants ≥2 months and Children ≤3 years: Oral: 125 mg twice daily.
Children >3 years: Oral: 250 mg twice daily.
Adolescents: Oral: 250 to 500 mg twice daily or 500 to 1,000 mg once daily.
Reconstitute powder for oral solution with appropriate amount of water as specified in the manufacturer’s labeling. Shake vigorously until dissolved.
Oral: Administer around-the-clock to promote less variation in peak and trough serum levels. Take on an empty stomach 1 hour before or 2 hours after meals, to enhance absorption.
Powder for oral solution: Store dry powder at 20°C to 25°C (68°F to 77°F). Reconstituted oral solution should be stored in refrigerator. Discard unused solution after 14 days (consult manufacturer labeling for specific recommendations).
Tablet: Store at 20°C to 25°C (68°F to 77°F).
Acemetacin: May increase the serum concentration of Penicillins. Monitor therapy
Aminoglycosides: Penicillins may decrease the serum concentration of Aminoglycosides. Primarily associated with extended spectrum penicillins, and patients with renal dysfunction. 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
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
Dichlorphenamide: Penicillins may enhance the hypokalemic effect of Dichlorphenamide. Monitor therapy
Lactobacillus and Estriol: Antibiotics may diminish the therapeutic effect of Lactobacillus and Estriol. Monitor therapy
Methotrexate: Penicillins may increase the serum concentration of Methotrexate. Monitor therapy
Mycophenolate: Penicillins may decrease serum concentrations of the active metabolite(s) of Mycophenolate. This effect appears to be the result of impaired enterohepatic recirculation. Monitor therapy
Nitisinone: May increase the serum concentration of OAT1/3 Substrates. Monitor therapy
Pretomanid: May increase the serum concentration of OAT1/3 Substrates. Monitor therapy
Probenecid: May increase the serum concentration of Penicillins. Monitor therapy
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
Teriflunomide: May increase the serum concentration of OAT1/3 Substrates. Monitor therapy
Tetracyclines: May diminish the therapeutic effect of Penicillins. Monitor therapy
Tolvaptan: May increase the serum concentration of OAT1/3 Substrates. Management: Avoid concomitant use of OAT1/3 substrates in patients receiving the Jynarque brand of tolvaptan. Concentrations and effects of the OAT1/3 substrate would be expected to increase with combined use. Consider therapy modification
Typhoid Vaccine: Antibiotics may diminish the therapeutic effect of Typhoid Vaccine. Only the live attenuated Ty21a strain is affected. Management: Vaccination with live attenuated typhoid vaccine (Ty21a) should be avoided in patients being treated with systemic antibacterial agents. Use of this vaccine should be postponed until at least 3 days after cessation of antibacterial agents. Consider therapy modification
Vitamin K Antagonists (eg, warfarin): Penicillins may enhance the anticoagulant effect of Vitamin K Antagonists. Monitor therapy
False-positive or negative urinary glucose determination using Clinitest®; positive Coombs' [direct]; false-positive urinary and/or serum proteins
>10%: Gastrointestinal: Melanoglossia, mild diarrhea, nausea, oral candidiasis, vomiting
<1%: Acute interstitial nephritis, anaphylaxis, convulsions, exfoliative dermatitis, fever, hemolytic anemia, hypersensitivity reaction, positive direct Coombs test, serum-sickness like reaction
Concerns related to adverse effects:
• Anaphylactic/hypersensitivity reactions: Serious and occasionally severe or fatal hypersensitivity (anaphylactic) reactions have been reported in patients on penicillin therapy, especially with a history of beta-lactam hypersensitivity or history of sensitivity to multiple allergens.). Use with caution in asthmatic patients. If a serious reaction occurs, treatment with supportive care measures and airway protection should be instituted immediately.
• 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.
• Renal impairment: Use with caution in patients with severe renal impairment.
• Seizure disorders: Use with caution in patients with a history of seizure disorder; high levels, particularly in the presence of renal impairment, may increase risk of seizures.
Concurrent drug therapy related issues:
• Drug-drug interactions: Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information.
Dosage form specific issues:
• Benzyl alcohol and derivatives: Some dosage forms may contain sodium benzoate/benzoic acid; benzoic acid (benzoate) is a metabolite of benzyl alcohol; large amounts of benzyl alcohol (≥99 mg/kg/day) have been associated with a potentially fatal toxicity (“gasping syndrome”) in neonates; the “gasping syndrome” consists of metabolic acidosis, respiratory distress, gasping respirations, CNS dysfunction (including convulsions, intracranial hemorrhage), hypotension, and cardiovascular collapse (AAP ["Inactive" 1997]; CDC, 1982); some data suggests that benzoate displaces bilirubin from protein binding sites (Ahlfors 2001); avoid or use dosage forms containing benzyl alcohol derivative with caution in neonates. See manufacturer’s labeling.
• Prolonged use: Extended duration of therapy or use associated with high serum concentrations (eg, in renal insufficiency) may be associated with an increased risk for some adverse reactions (neutropenia, hemolytic anemia, serum sickness).
Periodic renal and hematologic function tests during prolonged therapy; monitor for signs of anaphylaxis during first dose
Penicillin crosses the placenta (Heikkilä 1994).
Due to pregnancy-induced physiologic changes, some pharmacokinetic parameters of penicillin V may be altered in the second and third trimester (Heikkilä 1993).
Penicillin is widely used in pregnant women. Based on available data, penicillin is generally considered compatible for use during pregnancy (Ailes 2016; Bookstaver 2015; Crider 2009; Damkier 2019; Dencker 2002; Heikkilä 1994; Heinonen 1977; Lamont 2014; Muanda 2017a; Muanda 2017b).
Penicillin is recommended for the management of syphilis during pregnancy. Penicillin V is not recommended for treatment; however, it may be used in the desensitization protocol so that the appropriate penicillin formulation may then be used (CDC [Workowski 2015]; Dallé 2018).
If treatment for the management of Bacillus anthracis is needed in pregnant women, other agents are preferred (Meaney-Delman 2014).
What is this drug used for?
• It is used to treat or prevent bacterial infections.
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:
• Abdominal pain
• Tongue 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:
• 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.
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
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- Penicillin V (AHFS Monograph)
- Penicillin V Potassium (AHFS Monograph)
- Penicillin V (FDA)
- Penicillin V Potassium (FDA)