Acyclovir

Antiviral (Guanosine Analog)

Drug Class: Antiviral (Guanosine Analog)
Mechanism of Action (MOA): Phosphorylated by viral thymidine kinase → inhibits viral DNA polymerase.
Clinical Notes: HSV and VZV (not CMV). Crystal-induced nephrotoxicity — hydrate well. Valacyclovir is the better-absorbed prodrug.
Source: FDA label

Sources

Reviewed June 2026

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