A substance that is being studied in the prevention of fungal, bacterial, and viral infections in patients undergoing donor stem cell transplantation with cells that are infected with cytomegalovirus. It belongs to the family of drugs called antivirals.

one of three available antiviral drugs that can reduce the severity and duration of a shingles attack if given soon after onset.

a prodrug of acyclovir used as an antiherpes treatment. Valacyclovir has significantly greater bioavailability than acyclovir, and thus is effective at lower doses. (valtrex)