Acyclovir is one of a class of medicines known as antivirals. Acyclovir is used to treat infections caused by certain viruses. Topical acyclovir is used to treat the symptoms of herpes infections of the skin, mucous membranes, and genitals.
If you are taking Acyclovir to help control the symptoms of herpes, it is important to use rubber gloves when applying this medicine. This will keep you from spreading the infection. Apply enough medicine to completely cover all blisters.
Take Acyclovir for the entire time your doctor recommends, even if your symptoms begin to clear up. Do NOT use this medicine more often than your doctor tells you, or for a longer time than you should. If your symptoms show little or no improvement within a week, or if they should worsen, there is a possibility of viral resistance. Check with your doctor right away.
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.
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.
Tell your doctor if you have continuing problems with any of the following: mild pain, burning, or stinging; itching, stinging, or redness of the genital area; or skin rash.
ZOVIRAX is the brand name for acyclovir, a synthetic nucleoside analogue active against herpesviruses. ZOVIRAX Capsules, Tablets, and Suspension are formulations for oral administration. Each capsule of ZOVIRAX contains 200 mg of acyclovir and the inactive ingredients corn starch, lactose, magnesium stearate, and sodium lauryl sulfate. The capsule shell consists of gelatin, FD&C Blue No. 2, and titanium dioxide. May contain one or more parabens. Printed with edible black ink. Each 800-mg tablet of ZOVIRAX contains 800 mg of acyclovir and the inactive ingredients FD&C Blue No. 2, magnesium stearate, microcrystalline cellulose, povidone, and sodium starch glycolate. Each 400-mg tablet of ZOVIRAX contains 400 mg of acyclovir and the inactive ingredients magnesium stearate, microcrystalline cellulose, povidone, and sodium starch glycolate. Each teaspoonful (5 mL) of ZOVIRAX Suspension contains 200 mg of acyclovir and the inactive ingredients methylparaben 0.1% and propylparaben 0.02% (added as preservatives), carboxymethylcellulose sodium, flavor, glycerin, microcrystalline cellulose, and sorbitol. Acyclovir is a white, crystalline powder with the molecular formula C8H11N5O3 and a molecular weight of 225. The maximum solubility in water at 37° C is 2.5 mg/mL. The pka’s of acyclovir are 2.27 and 9.25. The chemical name of acyclovir is 2-amino-1,9-dihydro-9-[(2-hydroxyethoxy)methyl]-6H-purin-6-one.
Acyclovir has the following structural formula: