Acyclovir take how long to expel the virus is not conclusive, but clinical use for herpes simplex virus infection, the course of treatment is generally 10 days, for herpes zoster, the course of treatment is mostly 7 to 10 days. Acyclovir is an antiviral drug, in vitro inhibitory effect on cytomegalovirus, herpes simplex virus, varicella zoster virus, etc. It is clinically used for herpes simplex virus infections, herpes zoster in immunocompetent people, and chickenpox in immunodeficient people. Adverse reactions such as dizziness, headache, arthralgia, itchy skin, etc. may occur with acne, insomnia, menstrual disorders with prolonged use of Acyclovir. Use with caution in lactating women, Acyclovir is contraindicated in people who are allergic to the drug ingredients. Acyclovir should be used in accordance with medical advice, and should not be taken without authorization.