Journal of AIDS & Clinical Research

A Case of a Potential Drug Interaction between Phenobarbital and Darunavir-based Antiretroviral Therapy

Abstract

Mark Naccarato, Deborah Yoong, Ignatius Fong and Kevin Gough

The cytochrome P450 isoform that is primarily involved in the metabolism of darunavir is CYP3A4. Drugs that modulate this enzyme would then be expected to alter the pharmacokinetics of darunavir.Phenobarbital, a traditional antiepileptic has been shown to have broad induction effects on CYP450 and glucuronidation systems and would be expected to affect any drug, including antiretrovirals that are handled by these systems. We report a case in which we believe decreased serum concentrations of darunavir may have been a result of a drug interaction with phenobarbital.