Herpes zoster is a skin disease caused by infection with varicella zoster virus. Acyclovir is a more commonly used antiviral medication, which has a better inhibitory effect on herpes simplex and varicella zoster virus. The correct usage of acyclovir includes oral administration as well as local topical application. 1. Topical Acyclovir: Acyclovir cream is used by applying the drug directly to the lesion area, usually 4~5 times a day, or according to the change of the condition, the number of times of use can be increased appropriately. Adverse effects of the drug mainly include local burning and itching. 2. Oral acyclovir: acyclovir tablets are used as 0.8g once a day for adults, 5 times a day, and the dose can also be adjusted appropriately according to body weight and the severity of the disease. Adverse effects of the drug mainly include nausea, vomiting as well as stomach upset. Patients with shingles are advised to consult a doctor in a timely manner, and to avoid unauthorized use of medication under the guidance of a doctor.