acyclovir /əsī″klōvir/ , an antiviral agent with activity against herpesvirus types 1 and 2 and varicella zoster virus. Acyclovir is converted by a herpesvirus enzyme into a molecule (acyclovir triphosphate) that inhibits the synthesis of deoxyribonucleic acid (DNA) molecules in the virally infected cells, thereby inhibiting viral replication. ▪ INDICATIONS: It is prescribed topically in an ointment for the treatment of herpes simplex lesions (cold sores) and both orally and systemically (oral and IV) in other types of herpes infections, including genital herpes, herpes encephalitis, chickenpox (varicella zoster), and shingles (herpes zoster). ▪ CONTRAINDICATIONS: Known sensitivity to this drug prohibits its use. ▪ ADVERSE EFFECTS: After topical use, irritation or pruritus may occur; after systemic use, diaphoresis, headache, and nausea may occur. When it is administered intravenously in the treatment of immunosuppressed patients, there may be pain at the site of the injection, and 1% to 10% of such patients experience acute renal failure.
