Acyclovir tablets are antiviral drugs that can be used to treat herpes simplex, genital herpes, and herpes zoster. For the treatment of herpes simplex and genital herpes, for the primary form, acyclovir tablets are taken orally 200 mg 5 times/day or 400 mg 3 times/day for 7-10 days each time; for the relapsing form, intermittent therapy is used, preferably starting within 24 hours of the appearance of prodromal symptoms or lesions. Acyclovir tablets are given 200 mg 5 times/day or 400 mg 3 times/day orally for a typical duration of 5 days; for frequent relapsing type, that is, more than 6 relapses in 1 year, continuous suppressive therapy is used to reduce the number of relapses. Acyclovir tablets, 400 mg each time, 3 times/day, orally, are given and generally need to be taken orally for 6-12 months continuously. For the treatment of herpes zoster, antiviral therapy is usually started within 48-72 hours after the onset of the rash, i.e., acyclovir tablets 800 mg each time, 5 times/day, orally, for a course of 7 days.