The duration of Valtoval 500 Tablet treatment depends on the disease you are being treated for and whether your immune system is capable of fighting infections or not. For example, if you are taking it for shingles and your immune system works effectively, then you may need to take it for 7 days only. But, if your immunity is compromised, then you may need to take Valtoval 500 Tablet for 7 days and 2 days more after the lesions have dried and healed. Follow your doctor’s recommendations strictly.