Drug Interaction Report

MONITOR: The coadministration of perampanel with other antiepileptic medications that are inducers of CYP450 3A4 may significantly decrease the plasma concentrations and pharmacologic effects of perampanel, which is primarily metabolized by the isoenzyme. Reductions in the average steady state concentrations of perampanel have been reported with known CYP450 3A4 inducers such as carbamazepine (3-fold decrease), oxcarbazepine (2-fold decrease), phenytoin (2-fold decrease), and topiramate (20% decrease). In addition, a 35% increase was reported in oxcarbazepine concentration; however, its active metabolite was not measured.

MANAGEMENT: Pharmacologic effects of perampanel should be monitored more closely whenever a CYP450 3A4 inducer is added to or withdrawn from therapy, and the perampanel dosage adjusted as necessary according to the patient's clinical response.

GENERALLY AVOID: Alcohol may potentiate some of the pharmacologic effects of CNS-active agents. Use in combination may result in additive central nervous system depression and/or impairment of judgment, thinking, and psychomotor skills.

MANAGEMENT: Patients receiving CNS-active agents should be warned of this interaction and advised to avoid or limit consumption of alcohol. Ambulatory patients should be counseled to avoid hazardous activities requiring complete mental alertness and motor coordination until they know how these agents affect them, and to notify their physician if they experience excessive or prolonged CNS effects that interfere with their normal activities.