ZEVIN (Acyclovir) is a synthetic acyclic nucleoside analogue with in vitro inhibitory activity against Herpes simplex types 1 and 2 (HSV-1 and HSV-2), varicella-zoster, Epstein-Barr and cytomegalovirus. In cell cultures, the inhibitory activity of acyclovir for Herpes simplex virus is highly selective.
Acyclovir is poorly absorbed following oral administration, with peak plasma levels occuring in 1.7 hours. Acyclovir is metabolized in liver. Plasma protein-binding is low. The half-life is 3.3 hours. Approximately 14% of total dose excreted unchanged in urine. Absorption of acyclovir is usually slight following topical application to intact skin.
In disease skin (Herpes zoster), moderate plasma concentrations up to 0.28 mcg/ml have been reported in patients with normal renal function.
Approximately 9% of the total daily dose may be excreted in the urine.