Zovirax Cream is a prescription antiviral medication containing 5% aciclovir used to treat cold sores (herpes labialis) and genital herpes. The 10g cream formulation is designed for topical application and should be used under medical supervision. The active ingredient aciclovir works by stopping the herpes virus from multiplying. For best results, treatment should begin as early as possible when symptoms first appear. The cream should be applied 5 times daily for 4 days. Common side effects may include mild burning or stinging at the application site. This medication is typically prescribed for immunocompetent adults and adolescents 12 years of age and older. Store at room temperature below 25°C.