Oral valacyclovir, famciclovir, or acyclovir should be given to healthy people at risk of moderate to severe disease, including patients 12 years of age or older (18 years of age or older for famciclovir) With skin disorders (particularly eczema) With chronic lung disease Receiving long term salicylate therapy Receiving corticosteroids The dose is famciclovir 500 mg 3 times a day or valacyclovir 1 g 3 times a day for adults.