"The Food and Drug Administration (FDA) has approved the approval of Qutenza (capsaicin) 8% patch, a medicated skin patch that relieves the pain of post-herpetic neuralgia (PHN), a serious complication that can occur after a bout with shingles."...
(valacyclovir hydrochloride) Caplets
- Patient Information:
Details with Side Effects
VALTREX (valacyclovir hydrochloride) is the hydrochloride salt of the L-valyl ester of the antiviral drug acyclovir.
VALTREX (valacyclovir hydrochloride) 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-6oxo-9H-purin-9-yl)methoxy]ethyl ester, monohydrochloride. It has the following structural formula:
Valacyclovir hydrochloride is a white to off-white powder 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 pkas for valacyclovir hydrochloride are 1.90, 7.47, and 9.43.
What are the possible side effects of valacyclovir (Valtrex)?
Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Stop taking valacyclovir and call your doctor right away if you have any of the following signs of a serious side effect that can harm red blood cells:
- fever, easy bruising or bleeding;
- red spots on the skin (not related to herpes or chickenpox);
- bloody diarrhea, vomiting;
- pale or yellowed skin;
- weakness or fainting; or
- urinating less than usual or not at...
What are the precautions when taking valacyclovir hydrochloride (Valtrex)?
See also Side Effects section.
Before taking valacyclovir, tell your doctor or pharmacist if you are allergic to it; or to acyclovir; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: kidney problems.
This drug may rarely make you dizzy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Limit alcoholic beverages.
Older adults may be more sensitive to the side effects of this drug, especially mental/mood changes (such as confusion, agitation) and kidney...
Last reviewed on RxList: 1/24/2011
This monograph has been modified to include the generic and brand name in many instances.
Additional Valtrex Information
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You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
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