Co-administration of hepatitis C virus (HCV) direct-acting antivirals (DAAs) with anti-epileptics or mood stabilizers with cytochrome P450 (CYP) and/or drug transport-inducing properties is contraindicated due to concerns of subtherapeutic DAA levels that can lead to treatment failure and viral resistance. The recommended strategy is to change the interacting medication to a different agent that does not have inducing properties, but this is not always possible depending on the clinical scenario. We report on three patients who received DAAs for their HCV infection while remaining on the contraindicated anti-epileptic or mood stabilizer by utilizing CYP and drug transport inhibitors as pharmacokinetic enhancers to attempt to overcome the induction effects and maximize chances of achieving sustained virologic response (SVR). All patients achieved SVR despite the drug-drug interactions and there were no safety concerns. In patients facing this unique clinical quandary, the use of CYP and drug transport inhibitors appears to be a safe and possible strategy.
Keywords: cytochrome P450 enzyme inhibitor; cytochrome P450 inducer; drug interactions; hepatitis C.
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