Impairment of Diazepam Metabolism by Low-Dose Estrogen-Containing Oral-Contraceptive Steroids

Abstract

ORAL-CONTRACEPTIVE steroids continue to be used widely in the United States and elsewhere. The metabolism of concurrently ingested drugs that are oxidatively metabolized may be impaired in long-term users of oral contraceptives.^{1 , 2} If the oxidative metabolism of diazepam, for example, is altered as a result of long-term use of oral contraceptives, such an interaction may be clinically important, especially in view of the widespread use of both drugs. We report that long-term use of low-dose estrogen-containing oral contraceptives impairs diazepam clearance, greatly increasing the elimination half-life of diazepam.MethodsSubjectsEight healthy women with a mean age of 27 years . . .