Zovirax is one of the antiviral medicines. The main target of this drug is ti fight herpes virus. It's also fights cold sores, chicken pox, genital herpes, shingles. Zovirax may also be useful for other health problems, which are not described here. If you have an allergy to Zovirax or to some components it consists of don't use it. If you have an allergy to some drugs related to it such as valacyclovir you should also avoid using of it. You should be careful in using of Zovirax if you have problems with your immune system or kidney desease. You may use this medicine alone or in complex with others drugs. But it's strongly recommended to not use it with prescription and nonprescription drugs, dietary medicine, herbal drugs, gentamicin, cyclosporine, ibuprofen, amphotericin B, tacrolimus and others medicines. If you are going to be pregnant or already pregnant you should talk about using of Zovirax with your doctor. You should also ask your doctor if this medicine could be compound with other drugs you are taking. You should have consultancy with your doctor before using Zovirax to prevent negative effects.