A topical antiviral composition comprising acyclovir, penciclovir and/oromaciclovir in a glucocorticoid-freephar-maceutical carrier comprising 15 to 25 weight % propylene glycol and 10to 25 weight % isopropyl C12-C22 alkanoic ester. Thecompositions have utility in the treatment or prophylaxis of herpesvirusinfections. Clinical results demonstrate that treatmentcommencing at the prodromal stage can prevent the development of a classiccold sore lesion in a large proportion of patients.
