valacyclovir and Demerol hcl Interactions

Interactions between valacyclovir and Demerol hcl (meperidine)

meperidine and valacyclovir (Moderate Drug-Drug)

MONITOR: Acyclovir may increase the plasma concentrations of meperidine and normeperidine, the metabolite that has been associated with adverse effects such as lethargy, agitation, and seizures. The mechanism of interaction is unknown. Increased pharmacologic and adverse effects of meperidine may occur.

MANAGEMENT: Caution is recommended if meperidine is used with acyclovir or its prodrug, valacyclovir. Patients should be monitored for tremor, seizures, CNS and respiratory depression, and cardiac arrhythmias.