Acyclovir is mainly used to treat herpes viruses, such as herpes simplex virus or varicella-zoster virus. It can be taken orally for 5-7 days for herpes simplex virus and 7-10 days for herpes zoster. Be sure to visit a regular hospital before treatment and take it as prescribed by the doctor, do not take it orally on your own because acyclovir is mainly metabolized by the kidneys and may have an impact on kidney function. Especially for some old and weak people or people with underlying diseases such as high blood sugar and high blood pressure. It is necessary to check the kidney function before use and adjust the medication according to the kidney function. Moreover, the use of acyclovir requires 5 times a day, so it must be used in full amount and in full course. For acyclovir also need to pay attention in the treatment of shingles, must be taken orally in the first 3 days of the blisters will be more effective, if the blisters have appeared 7 days is not recommended to take orally, is meaningless.