Foscarnet is an antiviral medication that prevents certain virus cells from multiplying in your body.
Foscarnet is used to treat cytomegalovirus (CMV) retinitis in people with AIDS.
Foscarnet is also used to treat herpes simplex virus (HSV) in people with a weak immune system. Foscarnet is usually given for HSV after other antiviral medications have been tried without successful treatment. Foscarnet is not a cure for CMV or HSV, and your virus may progress during or after treatment.
