How does valacyclovir treat cold sores?

Valacyclovir is a prescription antiviral medicine. Your body changes it into acyclovir, which slows the herpes virus from making more copies. It treats viral activity during an outbreak. It does not remove the virus that remains in nerve cells, so future outbreaks are still possible.

Treatment may shorten an outbreak when started at the first warning signs, such as tingling or burning. Results vary. It is not an instant fix, and a sore may still develop after you start treatment. Taking medicine also does not mean you can no longer pass the virus to someone else.

A licensed physician in your state reviews your symptoms, health history, and other medicines before deciding whether valacyclovir is appropriate. Tell them about kidney disease, pregnancy, breastfeeding, and any past reaction to valacyclovir or acyclovir. Follow your prescription exactly rather than using leftover medicine or someone else's tablets. If outbreaks are frequent or especially painful, ask whether a different treatment approach or an in-person evaluation is needed.