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Drug Interactions between Camptosar and Farbital

This report displays the potential drug interactions for the following 2 drugs:

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Interactions between your drugs

Moderate

butalbital irinotecan

Applies to: Farbital (aspirin / butalbital / caffeine) and Camptosar (irinotecan)

MONITOR: Coadministration with inducers of the CYP450 3A4 isoenzyme may decrease the plasma concentrations of irinotecan and its pharmacologically active metabolite, SN-38. Irinotecan is partially metabolized by CYP450 3A4, and induction of this process results in less of the drug available in the plasma for conversion to SN-38 via carboxylesterases. The interaction has been reported with St. John's wort and the enzyme-inducing anticonvulsants carbamazepine, phenobarbital, and phenytoin. An approximately 40% reduction in SN-38 systemic exposure (AUC) has been reported in the presence of St. John's wort and greater than 60% reductions have been reported in the presence of enzyme-inducing anticonvulsants. However, all of these agents are known to be potent inducers of CYP450 3A4 as well as other enzymatic pathways (e.g., UDP-glucuronosyl transferase, or UGT; carboxylesterases) and drug transporters (e.g., multispecific organic anion transporter, or MRP2; P-glycoprotein) that may be involved in the clearance of irinotecan and/or SN-38. The extent, if any, to which irinotecan may interact with less potent CYP450 3A4 inducers is unknown.

MANAGEMENT: The antitumour activity of irinotecan may be reduced in patients treated with CYP450 3A4 inducers. Pharmacologic response to irinotecan should be monitored more closely whenever a CYP450 3A4 inducer is added to or withdrawn from therapy, and the irinotecan dosage adjusted as necessary.

References

  1. "Product Information. Camptosar (irinotecan)." Pharmacia and Upjohn PROD (2001):
  2. De Bruijn P, De Jonge MJ, Mathijssen RH, Sparreboom A, Verweij J "Modulation of irinotecan(CPT-11)metabolism by St. John's wort in cancer patients. http:aacr02.agora.com/planner/displayabstract.asp?presentationid=2603" (2002):
  3. Murry DJ, Cherrick I, Salama V, et al. "Influence of phenytoin on the disposition of irinotecan: a case report." J Pediatr Hematol Oncol 24 (2002): 130-3
  4. Mathijssen RH, Verweij J, De Bruijn P, Loos WJ, Sparreboom A "Effects of St. John's Wort on Irinotecan Metabolism." J Natl Cancer Inst 94 (2002): 1247-9
  5. Kuhn JG "Influence of anticonvulsants on the metabolism and elimination of irinotecan. A North American Brain Tumor Consortium preliminary report." Oncology (Williston Park 16(8 Suppl 7) (2002): 33-40
  6. Friedman HS, Petros WP, Friedman AH, et al. "Irinotecan therapy in adults with recurrent or progressive malignant glioma." J Clin Oncol 17 (1999): 1516-25
  7. Santos A, Zanetta S, Cresteil T, et al. "Metabolism of irinotecan (CPT-11) by CYP3A4 and CYP3A5 in humans." Clin Cancer Res 6 (2000): 2012-20
  8. Yonemori K, Takeda Y, Toyota E, Kobayashi N, Kudo K "Potential interactions between irinotecan and rifampin in a patient with small-cell lung cancer." Int J Clin Oncol 9 (2004): 206-9
  9. Innocenti F, Undevia SD, Ramirez J, et al. "A phase I trial of pharmacologic modulation of irinotecan with cyclosporine and phenobarbital." Clin Pharmacol Ther 76 (2004): 490-502
  10. Di YM, Li CG, Xue CC, Zhou SF "Clinical drugs that interact with St. John's wort and implication in drug development." Curr Pharm Des 14 (2008): 1723-42
  11. Crews KR, Stewart CF, Jones-Wallace D, et al. "Altered irinotecan pharmacokinetics in pediatric high-grade glioma patients receiving enzyme-inducing anticonvulsant therapy." Clin Cancer Res 8 (2002): 2202-9
  12. Radomski KM, Gajjar AJ, Kirstein MN, et al. "Irinotecan clearance is increased by concomitant administration of enzyme inducers in a patient with glioblastoma multiforme." Pharmacotherapy 20 (2000): 353
  13. Minami H, Lad TE, Nicholas MK, Vokes EE, Ratain MJ "Pharmacokinetics and pharmacodynamics of 9-aminocamptothecin infused over 72 hours in phase II studies." Clin Cancer Res 5 (1999): 1325-30
  14. Zamboni WC, Gajjar AJ, Heideman RL, et al. "Phenytoin alters the disposition of topotecan and N-desmethyl topotecan in a patient with medulloblastoma." Clin Cancer Res 4 (1998): 783-9
  15. "Product Information. Onivyde (irinotecan liposomal)." Merrimack Pharmaceuticals (2015):
View all 15 references

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Minor

aspirin caffeine

Applies to: Farbital (aspirin / butalbital / caffeine) and Farbital (aspirin / butalbital / caffeine)

One study has reported that coadministration of caffeine and aspirin lead to a 25% increase in the rate of appearance and 17% increase in maximum concentration of salicylate in the plasma. A significantly higher area under the plasma concentration time curve of salicylate was also reported when both drugs were administered together. The exact mechanism of this interaction has not been specified. Physicians and patients should be aware that coadministration of aspirin and caffeine may lead to higher salicylate levels faster.

References

  1. Yoovathaworn KC, Sriwatanakul K, Thithapandha A "Influence of caffeine on aspirin pharmacokinetics." Eur J Drug Metab Pharmacokinet 11 (1986): 71-6

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Drug and food interactions

Major

butalbital food

Applies to: Farbital (aspirin / butalbital / caffeine)

GENERALLY AVOID: Concurrent acute use of barbiturates and ethanol may result in additive CNS effects, including impaired coordination, sedation, and death. Tolerance of these agents may occur with chronic use. The mechanism is related to inhibition of microsomal enzymes acutely and induction of hepatic microsomal enzymes chronically.

MANAGEMENT: The combination of ethanol and barbiturates should be avoided.

References

  1. Gupta RC, Kofoed J "Toxological statistics for barbiturates, other sedatives, and tranquilizers in Ontario: a 10-year survey." Can Med Assoc J 94 (1966): 863-5
  2. Misra PS, Lefevre A, Ishii H, Rubin E, Lieber CS "Increase of ethanol, meprobamate and pentobarbital metabolism after chronic ethanol administration in man and in rats." Am J Med 51 (1971): 346-51
  3. Saario I, Linnoila M "Effect of subacute treatment with hypnotics, alone or in combination with alcohol, on psychomotor skills related to driving." Acta Pharmacol Toxicol (Copenh) 38 (1976): 382-92
  4. Stead AH, Moffat AC "Quantification of the interaction between barbiturates and alcohol and interpretation of fatal blood concentrations." Hum Toxicol 2 (1983): 5-14
  5. Seixas FA "Drug/alcohol interactions: avert potential dangers." Geriatrics 34 (1979): 89-102
View all 5 references

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Moderate

aspirin food

Applies to: Farbital (aspirin / butalbital / caffeine)

GENERALLY AVOID: The concurrent use of aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs) and ethanol may lead to gastrointestinal (GI) blood loss. The mechanism may be due to a combined local effect as well as inhibition of prostaglandins leading to decreased integrity of the GI lining.

MANAGEMENT: Patients should be counseled on this potential interaction and advised to refrain from alcohol consumption while taking aspirin or NSAIDs.

References

  1. "Product Information. Motrin (ibuprofen)." Pharmacia and Upjohn PROD (2002):

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Minor

caffeine food

Applies to: Farbital (aspirin / butalbital / caffeine)

The effect of grapefruit juice on the pharmacologic activity of caffeine is controversial. One report suggests that grapefruit juice increases the effect of caffeine. The proposed mechanism is inhibition of cytochrome P-450 metabolism of caffeine. However, a well-conducted pharmacokinetic/pharmacodynamic study did not demonstrate this effect. The clinical significance of this potential interaction is unknown.

References

  1. "Grapefruit juice interactions with drugs." Med Lett Drugs Ther 37 (1995): 73-4
  2. Maish WA, Hampton EM, Whitsett TL, Shepard JD, Lovallo WR "Influence of grapefruit juice on caffeine pharmacokinetics and pharmacodynamics." Pharmacotherapy 16 (1996): 1046-52

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Minor

aspirin food

Applies to: Farbital (aspirin / butalbital / caffeine)

One study has reported that coadministration of caffeine and aspirin lead to a 25% increase in the rate of appearance and 17% increase in maximum concentration of salicylate in the plasma. A significantly higher area under the plasma concentration time curve of salicylate was also reported when both drugs were administered together. The exact mechanism of this interaction has not been specified. Physicians and patients should be aware that coadministration of aspirin and caffeine may lead to higher salicylate levels faster.

References

  1. Yoovathaworn KC, Sriwatanakul K, Thithapandha A "Influence of caffeine on aspirin pharmacokinetics." Eur J Drug Metab Pharmacokinet 11 (1986): 71-6

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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.

See also

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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.

Further information

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

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