Explain Acyclovir

Available in topical, oral, and intravenous (IV) formulations, acyclovir is used to treat herpes simplex virus (HSV) and varicella-zoster virus (VZV) infections. Acyclovir cream reduces the duration of herpes labialis by about half a day. Oral acyclovir is effective for both primary and recurrent genital HSV infections. Long-term oral sup pression with acyclovir decreases the frequency of symptomatic genital recurrences and asymptomatic viral shedding. Oral acyclovir begun within 24 hours after the onset of rash, decreases the severity of primary varicella infection and can also be used to treat localized zoster. IV acyclovir is the drug of choice for treatment of HSV infections that are visceral, disseminated or contain the central nervous system (CNS) and for serious or disseminated VZV infections.