acyclovir (generic name)

It is used to treat or prevent infections caused by certain kinds of viruses
(ay SYE kloe veer)
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What is this medicine?

ACYCLOVIR (ay SYE kloe veer) is an antiviral medicine. It is used to treat or prevent infections caused by certain kinds of viruses. Examples of these infections include herpes and shingles. This medicine will not cure herpes.

What should I tell my health care provider before I take this medicine?

They need to know if you have any of these conditions:
  • kidney disease
  • an unusual or allergic reaction to acyclovir, ganciclovir, valacyclovir, other medicines, foods, dyes, or preservatives
  • pregnant or trying to get pregnant
  • breast-feeding

How should I use this medicine?

Take this medicine by mouth with a glass of water. Follow the directions on the prescription label. You can take it with or without food. Take your medicine at regular intervals. Do not take your medicine more often than directed. Take all of your medicine as directed even if you think your are better. Do not skip doses or stop your medicine early.

Talk to your pediatrician regarding the use of this medicine in children. While this drug may be prescribed for selected conditions, precautions do apply.

What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

What may interact with this medicine?

  • probenecid

What should I watch for while using this medicine?

Tell your doctor or health care professional if your symptoms do not improve. This medicine works best when started very early in the course of an infection. Begin treatment at the first signs of infection.

Drink 6 to 8 glasses of water or fluids every day while you are taking this medicine. This will help prevent side effects.

You can still pass chickenpox, shingles, or herpes to another person even while you are taking this medicine. Avoid contact with others as directed. Genital herpes is a sexually transmitted disease. Talk to your doctor about how to stop the spread of infection.

What side effects may I notice from receiving this medicine?

Side effects that you should report to your doctor or health care professional as soon as possible:
  • allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue
  • chest pain
  • confusion, hallucinations, tremor
  • dark urine
  • increased sensitivity to the sun
  • redness, blistering, peeling or loosening of the skin, including inside the mouth
  • seizures
  • trouble passing urine or change in the amount of urine
  • unusual bleeding or bruising, or pinpoint red spots on the skin
  • unusually weak or tired
  • yellowing of the eyes or skin

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

  • diarrhea
  • fever
  • headache
  • nausea, vomiting
  • stomach upset

Where should I keep my medicine?

Keep out of the reach of children.

Store at room temperature between 15 and 25 degrees C (59 and 77 degrees F). Throw away any unused medicine after the expiration date.

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Last Updated: March 04, 2009
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