Acyclovir comes as a tablet, a capsule, and a suspension (liquid) to take by mouth. It is usually taken with or without food two to five times a day for 5 to 10 days, starting as soon as possible after your symptoms begin. When acyclovir is used to prevent outbreaks of genital herpes, it is usually taken two to five times a day for up to 12 months. Take acyclovir at around the same times every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take acyclovir exactly as directed. Do not take more or less of it or take it more often or for a longer time than prescribed by your doctor.