Valacyclovir is used to treat infections caused by certain types of viruses. In children, it is used to treat cold sores around the mouth (caused by herpes simplex) and chickenpox (caused by varicella zoster). In adults, it is used to treat shingles (caused by herpes zoster) and cold sores around the mouth. The viruses that cause these infections continue to live in the body even between outbreaks. Valacyclovir is also used to treat outbreaks of genital herpes. Valacyclovir decreases the severity and length of these outbreaks. In people with frequent outbreaks, this medication is used to reduce the number of future episodes. It helps the sores heal faster, keeps new sores from forming, and decreases pain/itching. This medication may also help reduce how long pain remains after the sores heal. Read the Patient Information Leaflet if available from your pharmacist before you start taking valacyclovir and each time you get a refill. 24 hours after lesion onset) Suppressive therapy (immunocompetent patients): 1 g/day PO Suppressive therapy (immunocompetent patients with ≤9 recurrences annually): 500 mg/day PO; transmission reduction for source partner, 500 mg/day PO Suppressive therapy (HIV-infected patients): 500 mg PO q12hr Thrombotic thrombocytopenic purpura (TTP)/hemolytic uremic syndrome (HUS) reported in patients with advanced HIV disease and in allogenic bone marrow transplant and renal transplant recipients Acute renal failure (ARF) may occur, especially in elderly patients or those with underlying renal impairment receiving higher than recommended doses; use with caution in patients with renal impairment, the elderly, and/or patients receiving nephrotoxic drugs Treatment should begin with the earliest symptom (tingling, burning, itching) in cold sores; for genital herpes, it should begin at the first signs and symptoms (within 72 hours of onset of first diagnosis or 24 hours of onset of recurrent episodes); for herpes zoster, it should begin within 72 hours of onset of rash; for chicken pox, it should begin with the earliest sign or symptom Central nervous system (CNS) effects may occur (eg, agitation, hallucinations, confusion, encephalopathy); risk of CNS adverse effects is higher in elderly patients Adequately hydrate patient; decreased precipitation in renal tubules may occur Metabolized by liver; valacyclovir is rapidly and nearly completely converted to acyclovir and L-valine via first-pass effect; acyclovir is hepatically metabolized to a very small extent by aldehyde oxidase and by alcohol and aldehyde dehydrogenase (inactive metabolites) The above information is provided for general informational and educational purposes only. Individual plans may vary and formulary information changes. Contact the applicable plan provider for the most current information.
A 500-mg maternal dosage of VALTREX twice daily would provide a nursing infant with an oral acyclovir dosage of approximately 0.6 mg/kg/day. A standard valacyclovir dosage for recurrent genital herpes outbreaks is 500 mg. dosage used for a primary oral herpes outbreak -- 2,000 mg of valacyclovir.