Valtrex (generic: valacyclovir) is a prescription medication used to treat conditions caused by the herpes virus including cold sores, shingles, genital herpes outbreaks, and chicken pox. Valtrex belongs to a group of drugs called antivirals which work by preventing the virus from multiplying.

This medication comes in caplet form and is taken one to three times daily, with or without food.

Common side effects of Valtrex include headaches, nausea, stomach pains, and dizziness.