Also called Valacyclovir, Valtrex is used to treat the symptoms of shingles, a herpes virus infection of the skin, and to treat and prevent genital herpes infections.
Be sure to tell your doctor of any allergies you have whether it is to medication or food, preservatives, or dyes. Also tell your doctor of any other medications you are taking, including vitamins and supplements, and any medical conditions you may have.
It is very important that you take this medicine exactly as your doctor tells you to. Do not take more or less medicine than directed, and if you miss a dose of this medicine, take it as soon as you remember, unless it is almost time for your next dose. Do NOT double doses.
Check with your doctor as soon as possible if the following side effects occur: painful menstruation, including abdominal cramps, diarrhea, or nausea; black, tarry stools; chest pain; chills; cough; decreased frequency/output of urine; fever; flu-like symptoms; headache; lower back/side pain; reduced mental alertness; shortness of breath; unusual tiredness; yellow eyes or skin; changes in behavior; difficulty breathing or swallowing; fast, pounding, or irregular heartbeat; high blood pressure; itching; lightheadedness when getting up from lying or sitting; skin redness; hallucinations; skin rash; swelling or puffiness of face, hands, legs, or feet; or wheezing.
VALTREX Caplets are for oral administration. Each caplet contains valacyclovir hydrochloride equivalent to 500 mg or 1 gram valacyclovir and the inactive ingredients carnauba wax, colloidal silicon dioxide, crospovidone, FD&C Blue No. 2 Lake, hypromellose, magnesium stearate, microcrystalline cellulose, polyethylene glycol, polysorbate 80, povidone, and titanium dioxide. The blue, film-coated caplets are printed with edible white ink. The chemical name of valacyclovir hydrochloride is L-valine, 2-[(2-amino-1,6-dihydro-6-oxo-9 H-purin-9-yl)methoxy]ethyl ester, monohydrochloride. Valacyclovir hydrochloride is a white to off-whitepowder with the molecular formula C13H20N6O4·HCl and a molecular weight of 360.80. The maximum solubility in water at 25°C is 174 mg/mL. The pka’s for valacyclovir hydrochloride are 1.90, 7.47, and 9.43.
Valtrex has the following structural formula: