Drug Interactions between afatinib and carbamazepine
This report displays the potential drug interactions for the following 2 drugs:
- afatinib
- carbamazepine
Interactions between your drugs
carBAMazepine afatinib
Applies to: carbamazepine and afatinib
ADJUST DOSE: Coadministration with inducers of P-glycoprotein (P-gp) may decrease the plasma concentrations of afatinib, which is a substrate of the efflux transporter. In study subjects, administration of afatinib in combination with the P-gp inducer rifampin (600 mg once daily for 7 days) resulted in a 34% decrease in afatinib systemic exposure.
MANAGEMENT: For patients who require chronic therapy with a P-gp inducer, it may be necessary to increase the daily dose of afatinib by 10 mg as tolerated. The previous dose may be resumed 2 to 3 days after discontinuation of the P-gp inducer.
References (1)
- (2013) "Product Information. Gilotrif (afatinib)." Boehringer Ingelheim
Drug and food interactions
carBAMazepine food
Applies to: carbamazepine
GENERALLY AVOID: Alcohol may potentiate some of the pharmacologic effects of carbamazepine. Use in combination may result in additive central nervous system depression and/or impairment of judgment, thinking, and psychomotor skills.
In a small, randomized, crossover study, the administration of carbamazepine with grapefruit juice (compared to water) increased plasma drug concentrations by approximately 40%. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruits.
MANAGEMENT: Patients receiving carbamazepine should be advised to avoid or limit consumption of alcohol. Given the drug's narrow therapeutic index, patients receiving carbamazepine therapy should preferably avoid the regular consumption of grapefruits and grapefruit juice to prevent any undue fluctuations in plasma drug levels. Patients should be advised to report signs of carbamazepine toxicity (nausea, visual disturbances, dizziness, or ataxia) to their physicians.
References (3)
- (2002) "Product Information. Tegretol (carbamazepine)." Novartis Pharmaceuticals
- Garg SK, Kumar N, Bhargava VK, Prabhakar SK (1998) "Effect of grapefruit juice on carbamazepine bioavailability in patients with epilepsy." Clin Pharmacol Ther, 64, p. 286-8
- Bailey DG, Dresser GR, Kreeft JH, Munoz C, Freeman DJ, Bend JR (2000) "Grapefruit-felodipine interaction: Effect of unprocessed fruit and probable active ingredients." Clin Pharmacol Ther, 68, p. 468-77
afatinib food
Applies to: afatinib
ADJUST DOSING INTERVAL: Food may reduce the oral bioavailability of afatinib. According to the product labeling, administration of afatinib with a high-fat meal decreased peak plasma concentration (Cmax) by 50% and systemic exposure (AUC) by 39% compared to administration in the fasted state.
MANAGEMENT: Afatinib should be taken at least 1 hour before or 2 hours after a meal.
References (1)
- (2013) "Product Information. Gilotrif (afatinib)." Boehringer Ingelheim
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
Drug Interaction Classification
Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit. | |
Moderately clinically significant. Usually avoid combinations; use it only under special circumstances. | |
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. | |
No interaction information available. |
Further information
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
Check Interactions
To view an interaction report containing 4 (or more) medications, please sign in or create an account.
Save Interactions List
Sign in to your account to save this drug interaction list.