This treatment is for acute outbreaks of genital herpes only.
If taken within 5 days of the start of an outbreak, Aciclovir should shorten your outbreak by 1-2 days and make the symptoms less severe. It might even prevent the outbreak if taken early enough.
There is no cure for herpes, so it may return. This treatment does not affect how often you get future outbreaks, or how severe they will be. However, you can minimise the inconvenience and discomfort of the outbreaks by considering herpes suppression treatment.