, and the resulting acyclovir serum levels are much higher than those achieved with oral acyclovir. Pharmacokinetic studies reveal that a therapeutic drug level equivalent to acyclovir 800 mg five times daily can be achieved with 1000 mg valacyclovir given every 8 hours . Because of the improved bioavailability of valacyclovir compared with acyclovir, studies have evaluated less frequent dosing for patients with HSV infection. Valacyclovir is effective in the treatment of first-episode HSV infection at a dose of 500–1000 mg to twice daily, and in the treatment of recurrent HSV infection at a dose of 500 mg twice daily if initiated within the first 24 h of signs or symptoms. Therapy should be continued until all lesions are dry and crusted. Additionally, valacyclovir is effective as suppressive therapy at a dose of 250 mg twice daily, 500 mg once daily (for patients with fewer than 10 recurrences per year), and 1 g once daily (for patients with 10 or more recurrences per year) [). A study evaluating very high valacyclovir dosing (8 g/day) for suppression of CMV in patients with advanced HIV disease suggested a possible association between valacyclovir and the syndromes of thrombotic thrombocytopenic purpura and hemolytic-uremic syndrome (TTP/HUS). 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.
Valacyclovir belongs to the class of medications known as antivirals. It is used to treat a viral infection affecting the skin known as shingles (herpes zoster). It is also used to treat cold sores, and to treat and prevent recurrences of genital herpes. It works by interfering with the way the virus reproduces. Valacyclovir works by stopping the virus from multiplying and spreading to nearby healthy cells. It does not cure shingles, cold sores, or genital herpes, but it does help the sores to heal more quickly, and it relieves pain and discomfort. When used to prevent recurrences of herpes, it also reduces the risk of transmission (spreading) of the infection to others. Cold sores are painful and oozing, and they always seem to appear before that wedding or class reunion. Cold sores are typically caused by type 1 virus (HSV-1). Also called fever blisters, the small, fluid-filled lesions typically form near or on your lips and can cause symptoms such as tingling, itching, or burning. But in some cases, HSV-1 can cause sores on the genitals and type 2 virus (HSV-2) can cause sores on the mouth. But, because they’re caused by a virus, they can be treated with antiviral medications. Valtrex, which contains the active ingredient valacyclovir, can help your cold sores clear up faster. It can also reduce the number of cold sores you get. Read on to learn how Valtrex works and how to use it to treat your cold sores. Cold sores typically start to heal on their own within about four to six days. Although, the first cold sore you get will likely last longer. Most people don’t require treatment for their cold sores, but, in some cases, a doctor may prescribe an antiviral medication such as Valtrex.
VALTREX Caplets blue, film─coated, capsule─shaped tablets, with a partial scorebar on both sides containing valacyclovir hydrochloride equivalent to 1 gram valacyclovir and printed with "VALTREX 1 gram." Bottle of 30 NDC 0173-0565-04. Bottle of 90 NDC 0173-0565-10. How Much Valacyclovir Valtrex Should You Take During a Herpes Outbreak. lower your risk of transmitting HSV-1 or HSV-2 to others during an outbreak.