Rifampin-Induced Methadone Withdrawal

Abstract

Rifampin alters the clinical efficacy of oral contraceptive and anticoagulant drugs by mechanisms not completely understood. These effects may be due in part to acceleration of their elimination by enhancement of hepatic microsomal drug-metabolizing enzyme activities.1 , 2 Several patients in the Bellevue Chest Service Methadone Maintenance Program complained of the onset of withdrawal symptoms when rifampin was administered for treatment of tuberculosis. None of the patients who received isoniazid or ethambutol (or both) had symptoms of withdrawal once stabilized on methadone maintenance, but in a majority of the patients receiving rifampin withdrawal symptoms developed. Since the isoniazid-rifampin regimen is the most . . .