Herpes refers to a group of viruses that cause a variety of herpes infections including genital herpes, shingles, chicken pox (also chickenpox), cold sores, and encephalitis (inflammation of the brain). -Acyclovir is the drug of choice for local and disseminated herpes simplex in HIV-infected and exposed infants and children; children with severe immunosuppression and moderate to severe lesions should be treated initially with IV therapy and may require longer therapy. Acyclovir is an antiviral drug. It slows the growth and spread of the herpes virus in the body. It will not cure herpes, but it can lessen the symptoms of the infection. The recommended treatment for herpes simplex encephalitis (HSE) remains intravenous acyclovir. In resource-poor countries, however, intravenous formulations are usually unavailable or unaffordable. Abstract. Acyclovir resistance is rarely seen in herpes simplex virus (HSV) type I encephalitis. Prevalence rates vary between 0.5 % in immunocompetent patients (Christophers et al. 1998; Fife et al. 1994) and 3.5–10 % in immunocompromised patients (Stranska et al. 2005). Herpes simplex encephalitis resolved after treatment with foscarnet. To our knowledge, this is the first report of acyclovir-resistant herpes simplex virus encephalitis in an immunocompetent, previously therapy-naive adult. The German trial of Acyclovir and Corticosteroids in Herpes-simplex-virus-Encephalitis (GACHE), a multicenter, randomized, placebo-controlled trial, is currently enrolling patients with HSE in a study designed to assess the outcomes of treatment with acyclovir against the outcomes of treatment with acyclovir plus dexamethasone. Medscape - Herpes simplex, zoster-specific dosing for Zovirax (acyclovir), frequency-based adverse effects, comprehensive interactions, contraindications, pregnancy & lactation schedules, and cost information. For herpes simplex, use normal oral dose every 12 hours if eGFR less than 10 mL/minute/1.73 m 2. With intravenous use in children Use normal intravenous dose every 12 hours if estimated glomerular filtration rate 25–50 mL/minute/1.73 m 2 (every 24 hours if estimated glomerular filtration rate 10–25 mL/minute/1.73 m 2. Herpes Simplex Encephalitis (HSE) is a rare but severe infection of the central nervous system associated with the presence of the 'Herpes Simplex Virus Type 1' (HSV-1).