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Drug Interactions between clopidogrel and IsonaRif

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Major

rifAMPin isoniazid

Applies to: IsonaRif (isoniazid / rifampin) and IsonaRif (isoniazid / rifampin)

MONITOR CLOSELY: The risk of hepatotoxicity is greater when rifampin and isoniazid (INH) are given concomitantly, than when either drug is given alone. The proposed mechanism is rifampin's induction of isoniazid hydrolase, an enzyme involved in the conversion of INH to isonicotinic acid and hydrazine. Hydrazine is the proposed toxic metabolite of INH, which has been shown in animal studies to cause steatosis, hepatocyte vacuolation and glutathione depletion. Some studies have also shown that slow acetylators have a two-fold increased risk of developing antituberculosis drug-induced hepatotoxicity (ATDH) as compared with fast acetylators due to more available INH for direct hydrolysis to hydrazine. Theoretically, a similar reaction may occur with rifabutin and isoniazid. Additional risk factors for developing hepatotoxicity include patients with advanced age, malnutrition, existing hepatic impairment, daily alcohol consumption, female gender, HIV infection, extra-pulmonary tuberculosis and/or patients who are taking other potent CYP450-inducing agents.

MANAGEMENT: Caution and close monitoring should be considered if isoniazid (INH) is coadministered with rifampin or rifabutin. In cases where coadministration is required, careful monitoring of liver function, especially ALT and AST, should be done at baseline and then every 2 to 4 weeks during therapy, or in accordance with individual product labeling. Some manufacturers of INH recommend strongly considering its discontinuation if serum aminotransferase concentrations (AST or SGOT, ALT or SGPT) exceed 3 to 5 times the upper limit of normal. Product labeling for rifampin also recommends the immediate discontinuation of therapy if hepatic damage is suspected. INH product labeling suggests alternate drugs be used if hepatitis is attributed to INH in patients with tuberculosis. However, if INH must be used, it should only be resumed after the patient's symptoms and laboratory abnormalities have cleared. It should also be restarted in very small, gradually increasing doses and immediately withdrawn if there is any indication of recurrent liver involvement. Patients should be counseled to immediately report signs or symptoms consistent with liver damage and notified that prodromal symptoms usually consist of fatigue, weakness, malaise, anorexia, nausea, and/or vomiting.

References

  1. O'Brien RJ, Long MW, Cross FS, et al. (1983) "Hepatotoxicity from isoniazid and rifampin among children treated for tuberculosis." Pediatrics, 72, p. 491-9
  2. Kumar A, Misra PK, Mehotra R, et al. (1991) "Hepatotoxicity of rifampin and isoniazid." Am Rev Respir Dis, 143, p. 1350-2
  3. Abadie-Kemmerly S, Pankey GA, Dalvisio JR (1988) "Failure of ketoconazole treatment of blastomyces dermatidis due to interaction of isoniazid and rifampin." Ann Intern Med, 109, p. 844-5
  4. Acocella G, Bonollo L, Garimoldi M, et al. (1972) "Kinetics of rifampicin and isoniazid administered alone and in combination to normal subjects and patients with liver disease." Gut, 13, p. 47-53
  5. Yamamoto T, Suou T, Hirayama C (1986) "Elevated serum aminotransferase induced by isoniazid in relation to isoniazid acetylator phenotype." Hepatology, 6, p. 295-8
  6. Steele MA, Burk RF, Des Prez RM (1991) "Toxic hepatitis with isoniazid and rifampin." Chest, 99, p. 465-71
  7. "Product Information. INH (isoniazid)." Ciba Pharmaceuticals, Summit, NJ.
  8. Sarma G, Immanuel C, Kailasam S, Narayana AS, Venkatesan P (1986) "Rifampin-induced release of hydrazine from isoniazid." Am Rev Respir Dis, 133, p. 1072-5
  9. (2001) "Product Information. Mycobutin (rifabutin)." Pharmacia and Upjohn
  10. (2001) "Product Information. Rifadin (rifampin)." Hoechst Marion Roussel
  11. Askgaard DS, Wilcke T, Dossing M (1995) "Hepatotoxicity caused by the combined action of isoniazid and rifampicin." Thorax, 50, p. 213-4
  12. Cerner Multum, Inc. "UK Summary of Product Characteristics."
  13. Canadian Pharmacists Association (2006) e-CPS. http://www.pharmacists.ca/function/Subscriptions/ecps.cfm?link=eCPS_quikLink
  14. Cerner Multum, Inc. "Australian Product Information."
  15. (2023) "Product Information. Isoniazid (isoniazid)." Chartwell RX, LLC.
  16. (2023) "Product Information. Isoniazid (Arrotex) (isoniazid)." Arrotex Pharmaceuticals Pty Ltd
  17. (2023) "Product Information. Isoniazid (isoniazid)." RPH Pharmaceuticals AB
  18. Sarma GR, Immanual C, Kailasam S, Narayana AS, Venkatesan P (2024) Rifampin-induced release of hydrazine from isoniazid. A possible cause of hepatitis during treatment of tuberculosis with regimens containing isoniazid and rifampin https://pubmed.ncbi.nlm.nih.gov/3717759/
  19. Tostmann A, Boeree MJ, Aarnoutse RE, De Lange WCM, Van Der Ven AJAM, Dekhuijzen R (2024) Antituberculosis drug-induced hepatotoxicity: concise up-to-date review https://onlinelibrary.wiley.com/doi/10.1111/j.1440-1746.2007.05207.x
  20. (2021) "Product Information. Isotamine (isoniazid)." Bausch Health, Canada Inc.
  21. (2022) "Product Information. Rifampin (rifAMPin)." Akorn Inc
  22. (2022) "Product Information. Rifampicin (rifampicin)." Mylan Pharmaceuticals Inc
  23. (2023) "Product Information. Rifadin (rifampicin)." Sanofi
  24. (2024) "Product Information. Rifadin (rifaMPICin)." Sanofi-Aventis Australia Pty Ltd
  25. (2019) "Product Information. Rofact (rifampin)." Bausch Health, Canada Inc.
View all 25 references

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Moderate

rifAMPin clopidogrel

Applies to: IsonaRif (isoniazid / rifampin) and clopidogrel

GENERALLY AVOID: Coadministration with potent inducers of CYP450 2C19 may enhance the metabolic activation of clopidogrel, resulting in increased platelet inhibition and possibly bleeding risk. Clopidogrel is a prodrug that is converted to its active metabolite (AM) primarily by CYP450 2C19, with contributions from several other CYP450 isoenzymes including CYP450 3A, 2B6, and 1A2. When clopidogrel (600 mg loading dose followed by 75 mg once daily for 7 days) was coadministered with the potent CYP450 2C19 and 3A4 inducer rifampin (300 mg twice daily for 14 days) in twelve healthy volunteers, mean clopidogrel AM peak plasma concentration (Cmax) and systemic exposure (AUC) increased by approximately 3.8-fold. Mean inhibition of platelet aggregation at 4 hours post loading dose was 34% higher in the presence of rifampin compared to clopidogrel administered alone. When clopidogrel (75 mg once daily for 6 days) was coadministered with rifampin (300 mg twice daily for 10 days) in another study of ten healthy volunteers, platelet aggregation was 33% as compared to 56% following clopidogrel alone for 6 days and 94% at baseline.

MANAGEMENT: Concomitant use of clopidogrel with potent CYP450 2C19 inducers should be avoided when possible. If coadministration is required, patients should be monitored closely for signs of bleeding.

References

  1. Lau WC, Waskell LA, Watkins PB, et al. (2003) "Atorvastatin reduces the ability of clopidogrel to inhibit platelet aggregation: a new drug-drug interaction." Circulation, 107, p. 32-7
  2. Lau WC, Gurbel PA, Watkins PB, et al. (2004) "Contribution of hepatic cytochrome P450 3A4 metabolic activity to the phenomenon of clopidogrel resistance." Circulation, 109, p. 166-71
  3. Cerner Multum, Inc. "UK Summary of Product Characteristics."
  4. Cerner Multum, Inc. "Australian Product Information."
  5. Judge HM, Patil SB, Buckland RJ, Jakubowski JA, Storey RF (2010) "Potentiation of clopidogrel active metabolite formation by rifampicin leads to greater P2Y12 receptor blockade and inhibition of platelet aggregation after clopidogrel." J Thromb Haemost, 8, p. 1820-7
View all 5 references

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Moderate

isoniazid clopidogrel

Applies to: IsonaRif (isoniazid / rifampin) and clopidogrel

MONITOR: Coadministration with inhibitors of CYP450 2C19 may reduce the efficacy of clopidogrel, whose antiplatelet effect is dependent in part on bioactivation by the isoenzyme to a pharmacologically active metabolite. This is consistent with studies that reported decreased effectiveness of clopidogrel and poorer clinical outcome in patients who have common genetic polymorphisms of CYP450 2C19 resulting in reduced or absent enzyme activity. The interaction has been studied with omeprazole, a potent CYP450 2C19 inhibitor. In 72 healthy subjects administered clopidogrel (300 mg loading dose followed by 75 mg/day) alone and with omeprazole (80 mg) simultaneously for 5 days, systemic exposure to the active metabolite of clopidogrel decreased by 46% (Day 1) and 42% (Day 5) during coadministration with omeprazole, while mean inhibition of platelet aggregation (IPA) diminished by 47% (24 hours) and 30% (Day 5). Similar results were reported when the same doses of clopidogrel and omeprazole were administered 12 hours apart in another study. Data are not available for less potent inhibitors of CYP450 2C19. However, ineffective inhibition of platelet aggregation has been reported in association with a potential interaction with amiodarone, whose active metabolite, desethylamiodarone, has been shown to inhibit CYP450 2C19 in vitro.

MANAGEMENT: Based on existing data, it may be advisable to closely monitor the therapeutic efficacy of clopidogrel during concomitant treatment with CYP450 2C19 inhibitors.

References

  1. (2002) "Product Information. Cordarone (amiodarone)." Wyeth-Ayerst Laboratories
  2. (2001) "Product Information. Plavix (clopidogrel)." Bristol-Myers Squibb
  3. Ohyama K, Nakajima M, Suzuki M, Shimada N, Yamazaki H, Yokoi T (2000) "Inhibitory effects of amiodarone and its N-deethylated metabolite on human cytochrome P450 activities: Prediction of in vivo drug interactions." Br J Clin Pharmacol, 49, p. 244-53
  4. Hulot JS, Bura A, Villard E, et al. (2006) "Cytochrome P450 2C19 loss-of-function polymorphism is a major determinant of clopidogrel responsiveness in healthy subjects." Blood
  5. Gilard M, Arnaud B, Le Gal G, Abgrall JF, Boschat J (2006) "Influence of omeprazol on the antiplatelet action of clopidogrel associated to aspirin." J Thromb Haemost, 4, p. 2508-9
  6. Small DS, Farid NA, Payne CD, et al. (2008) "Effects of the proton pump inhibitor lansoprazole on the pharmacokinetics and pharmacodynamics of prasugrel and clopidogrel." J Clin Pharmacol, 48, p. 475-84
  7. Frere C, Cuisset T, Morange PE, et al. (2008) "Effect of Cytochrome P450 Polymorphisms on Platelet Reactivity After Treatment With Clopidogrel in Acute Coronary Syndrome." Am J Cardiol, 101, p. 1088-1093
  8. Gilard M, Arnaud B, Cornily JC, et al. (2008) "Influence of omeprazole on the antiplatelet action of clopidogrel associated with aspirin: the randomized, double-blind OCLA (Omeprazole CLopidogrel Aspirin) study." J Am Coll Cardiol, 51, p. 256-60
  9. Pezalla E, Day D, Pulliadath I (2008) "Initial assessment of clinical impact of a drug interaction between clopidogrel and proton pump inhibitors." J Am Coll Cardiol, 52, p. 1038-9
  10. Siller-Matula JM, Spiel AO, Lang IM, Kreiner G, Christ G, Jilma B (2009) "Effects of pantoprazole and esomeprazole on platelet inhibition by clopidogrel." Am Heart J, 157, 148.e1-5
  11. (2009) "Product Information. Kapidex (dexlansoprazole)." Takeda Pharmaceuticals America
  12. Juurlink DN, Gomes T, Ko DT, et al. (2009) "A population-based study of the drug interaction between proton pump inhibitors and clopidogrel." CMAJ, 180, p. 713-8
  13. Li XQ, Andersson TB, Ahlstrom M, Weidolf L (2004) "Comparison of inhibitory effects of the proton pump-inhibiting drugs omeprazole, esomeprazole, lansoprazole, pantoprazole, and rabeprazole on human cytochrome P450 activities." Drug Metab Dispos, 32, p. 821-7
  14. Collet JP, Hulot JS, Pena A, et al. (2009) "Cytochrome P450 2C19 polymorphism in young patients treated with clopidogrel after myocardial infarction: a cohort study." Lancet, 373, p. 309-17
  15. Mega JL, Close SL, Wiviott SD, et al. (2009) "Cytochrome p-450 polymorphisms and response to clopidogrel." N Engl J Med, 360, p. 354-62
  16. Lau WC, Gurbel PA (2009) "The drug-drug interaction between proton pump inhibitors and clopidogrel." CMAJ, 180, p. 699-700
  17. Moayyedi P, Sadowski DC (2009) "Proton pump inhibitors and clopidogrel -- hazardous drug interaction or hazardous interpretation of data?" Can J Gastroenterol, 23, p. 251-2
  18. Simon T, Verstuyft C, Mary-Krause M, et al. (2009) "Genetic determinants of response to clopidogrel and cardiovascular events." N Engl J Med, 360, p. 363-75
  19. Varenhorst C, Janes S, Erlinge D, et al. (2009) "Genetic variation of CYP2C19 affects both pharmacokinetic and pharmacodynamic responses to clopidogrel but not prasugrel in aspirin-treated patients with coronary artery disease." Eur Heart J, 30, p. 1744-52
View all 19 references

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Drug and food interactions

Moderate

rifAMPin food

Applies to: IsonaRif (isoniazid / rifampin)

GENERALLY AVOID: Concurrent use of rifampin in patients who ingest alcohol daily may result in an increased incidence of hepatotoxicity. The increase in hepatotoxicity may be due to an additive risk as both alcohol and rifampin are individually associated with this adverse reaction. However, the exact mechanism has not been established.

ADJUST DOSING INTERVAL: Administration with food may reduce oral rifampin absorption, increasing the risk of therapeutic failure or resistance. In a randomized, four-period crossover phase I study of 14 healthy male and female volunteers, the pharmacokinetics of single dose rifampin 600 mg were evaluated under fasting conditions and with a high-fat meal. Researchers observed that administration of rifampin with a high-fat meal reduced rifampin peak plasma concentration (Cmax) by 36%, nearly doubled the time to reach peak plasma concentration (Tmax) but reduced overall exposure (AUC) by only 6%.

MANAGEMENT: The manufacturer of oral forms of rifampin recommends administration on an empty stomach, 30 minutes before or 2 hours after meals. Patients should be encouraged to avoid alcohol or strictly limit their intake. Patients who use alcohol and rifampin concurrently or have a history of alcohol use disorder may require additional monitoring of their liver function during treatment with rifampin.

References

  1. (2022) "Product Information. Rifampin (rifAMPin)." Akorn Inc
  2. (2022) "Product Information. Rifampicin (rifampicin)." Mylan Pharmaceuticals Inc
  3. (2023) "Product Information. Rifadin (rifampicin)." Sanofi
  4. (2024) "Product Information. Rifadin (rifaMPICin)." Sanofi-Aventis Australia Pty Ltd
  5. Peloquin CA, Namdar R, Singleton MD, Nix DE (2024) Pharmacokinetics of rifampin under fasting conditions, with food, and with antacids https://pubmed.ncbi.nlm.nih.gov/9925057/
  6. (2019) "Product Information. Rofact (rifampin)." Bausch Health, Canada Inc.
View all 6 references

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Moderate

isoniazid food

Applies to: IsonaRif (isoniazid / rifampin)

GENERALLY AVOID: Concurrent use of isoniazid (INH) in patients who ingest alcohol daily may result in an increased incidence of both hepatotoxicity and peripheral neuropathy. The increase in hepatotoxicity may be due to an additive risk as both alcohol and INH are individually associated with this adverse reaction. INH-associated hepatotoxicity is believed to be due to an accumulation of toxic metabolites and may also be partly immune mediated, though the exact mechanisms are not universally agreed upon. INH is metabolized by N-acetyltransferase and CYP450 2E1. The rate of acetylation is genetically determined and generally classified as slow or rapid. Slow acetylators have been identified by some studies as having a higher risk of hepatotoxicity; therefore, this interaction may be more significant for patients who fall into this category. Other studies have postulated that alcohol-mediated CYP450 2E1 induction may play a role, as this isoenzyme is involved in INH metabolism and may be responsible for producing hepatotoxic metabolites. However, available literature is conflicting. The labeling for some INH products lists daily alcohol use or chronic alcoholism as a risk factor for hepatitis, but not all studies have found a significant association between alcohol use and INH-induced hepatotoxicity. Additionally, INH and alcohol are both associated with pyridoxine (B6) deficiency, which may increase the risk of peripheral neuropathy.

GENERALLY AVOID: Concomitant administration of isoniazid (INH) with foods containing tyramine and/or histamine may increase the risk of symptoms relating to tyramine- and/or histamine toxicity (e.g., headache, diaphoresis, flushing, palpitations, and hypotension). The proposed mechanism is INH-mediated inhibition of monoamine oxidase (MAO) and diamine oxidase (DAO), enzymes responsible for the metabolism of tyramine and histamine, respectively. Some authors have suggested that the reactions observed are mainly due to INH's effects on DAO instead of MAO or the amounts of histamine instead of tyramine present in the food. A Japanese case report recorded an example in 8 out of 25 patients on the tuberculosis ward who developed an accidental histamine poisoning after ingesting a fish paste (saury). Patients developed allergy-like symptoms, which started between 20 minutes and 2 hours after ingesting the food. A high-level of histamine (32 mg/100 g of fish) was confirmed in the saury paste and all 8 patients were both on INH and had reduced MAO concentrations. The 17 remaining patients were not on INH (n=5) or reported not eating the saury paste (n=12).

ADJUST DOSING INTERVAL: Administration with food significantly reduces oral isoniazid (INH) absorption, increasing the risk of therapeutic failure or resistance. The mechanism is unknown. Pharmacokinetic studies completed in both healthy volunteers (n=14) and tuberculosis patients (n=20 treatment-naive patients during days 1 to 3 of treatment) have resulted in almost doubling the time to reach INH's maximum concentration (tmax) and a reduction in isoniazid's maximum concentration (Cmax) of 42%-51% in patients who consumed high-fat or high-carbohydrate meals prior to INH treatment.

MANAGEMENT: The manufacturer of oral forms of isoniazid (INH) recommends administration on an empty stomach (i.e., 30 minutes before or 2 hours after meals). Patients should be encouraged to avoid alcohol or strictly limit their intake. Patients who use alcohol and INH concurrently or have a history of alcohol use disorder may require additional monitoring of their liver function during treatment with INH. Concomitant pyridoxine (B6) administration is also recommended to reduce the risk of peripheral neuropathy, with some authorities suggesting a dose of at least 10 mg/day. Patients should be advised to avoid foods containing tyramine (e.g., aged cheese, cured meats such as sausages and salami, fava beans, sauerkraut, soy sauce, beer, or red wine) or histamine (e.g., skipjack, tuna, mackerel, salmon) during treatment with isoniazid. Consultation of product labeling for combination products containing isoniazid and/or relevant guidelines may be helpful for more specific recommendations.

References

  1. Smith CK, Durack DT (1978) "Isoniazid and reaction to cheese." Ann Intern Med, 88, p. 520-1
  2. Dimartini A (1995) "Isoniazid, tricyclics and the ''cheese reaction''." Int Clin Psychopharmacol, 10, p. 197-8
  3. Uragoda CG, Kottegoda SR (1977) "Adverse reactions to isoniazid on ingestion of fish with a high histamine content." Tubercle, 58, p. 83-9
  4. Self TH, Chrisman CR, Baciewicz AM, Bronze MS (1999) "Isoniazid drug and food interactions." Am J Med Sci, 317, p. 304-11
  5. (2021) "Product Information. Isoniazid/Rifapentine 300 mg/300 mg (Macleods) (isoniazid-rifapentine)." Imported (India), 2
  6. (2023) "Product Information. Isoniazid (isoniazid)." Chartwell RX, LLC.
  7. (2023) "Product Information. Isoniazid (Arrotex) (isoniazid)." Arrotex Pharmaceuticals Pty Ltd
  8. (2023) "Product Information. Isoniazid (isoniazid)." RPH Pharmaceuticals AB
  9. Saukkonen JJ, Cohn DL, Jasmer RM, et al. (2006) "An official ATS statement: hepatotoxicity of antituberculosis therapy." Am J Respir Crit Care Med, 174, p. 935-52
  10. Bouazzi OE, Hammi S, Bourkadi JE, et al. (2024) First line anti-tuberculosis induced hepatotoxicity: incidence and risk factors. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5326068/
  11. Wang P, Pradhan K, Zhong XB, Ma X (2016) "Isoniazid metabolism and hepatoxicity." Acta Pharm Sin B, 6, p. 384-92
  12. Saktiawati AM, Sturkenboom MG, Stienstra Y, et al. (2016) "Impact of food on the pharmacokinetics of first-line anti-TB drugs in treatment naive TB patients: a randomized cross-over trial." J Antimicrob Chemother, 71, p. 703-10
  13. Hahn JA, Ngabirano C, Fatch R, et al. (2023) "Safety and tolerability of isoniazid preventive therapy for tuberculosis for persons with HIV with and without alcohol use." AIDS, 37, p. 1535-43
  14. Huang YS, Chern HD, Su WJ, et al. (2003) "Cytochrome P450 2E1 genotype and the susceptibility to antituberculosis drug-induced hepatitis." Hepatology, 37, p. 924-30
  15. Sousou JM, Griffith EM, Marsalisi C, Reddy P (2024) Pyridoxine deficiency and neurologic dysfunction: an unlikely association. https://www.cureus.com/articles/188310-pyridoxine-deficiency-and-neurologic-dysfunction-an-unlikely-association?score_article=true#!/
  16. Miki M, Ishikawa T, Okayama H (2005) "An outbreak of histamine poisoning after ingestion of the ground saury paste in eight patients taking isoniazid in tuberculous ward." Intern Med, 44, p. 1133-6
  17. (2021) "Product Information. Isotamine (isoniazid)." Bausch Health, Canada Inc.
View all 17 references

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Therapeutic duplication warnings

No warnings were found for your selected drugs.

Therapeutic duplication warnings are only returned when drugs within the same group exceed the recommended therapeutic duplication maximum.

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Drug Interaction Classification

These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
Unknown No interaction information available.

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