Zovirax, with the active ingredient acyclovir, belongs to a class of medications known as antivirals. It is specifically designed to treat viral infections, particularly those caused by the herpes simplex virus types 1 and 2, varicella-zoster virus (which causes chickenpox and shingles), and, in some cases, Epstein-Barr virus. Zovirax works by disrupting the virus’s ability to replicate, which helps to minimize the symptoms of the infection and accelerate the healing process.