Drug Interaction Report

MONITOR: Coadministration with rucaparib may increase the plasma concentrations and the risk of adverse effects of drugs that are substrates of CYP450 3A4. The proposed mechanism is decreased clearance due to rucaparib-mediated inhibition of CYP450 3A4. In a clinical study, rucaparib increased midazolam Cmax and AUC by 1.13- and 1.38-fold, respectively.

MANAGEMENT: Caution is advised if rucaparib is used concomitantly with drugs that are substrates of CYP450 3A4, particularly those with a narrow therapeutic range. Dosage adjustments as well as clinical and laboratory monitoring should be considered whenever rucaparib is added to or withdrawn from therapy with these drugs. Patients should be monitored for the development of adverse effects.

GENERALLY AVOID: Acute ethanol ingestion may potentiate the CNS effects of many benzodiazepines. Tolerance may develop with chronic ethanol use. The mechanism may be decreased clearance of the benzodiazepines because of CYP450 hepatic enzyme inhibition. Also, it has been suggested that the cognitive deficits induced by benzodiazepines may be increased in patients who chronically consume large amounts of alcohol.

MANAGEMENT: Patients should be advised to avoid alcohol during benzodiazepine therapy.