Proper Use

Drug information provided by: Merative, Micromedex®

Valacyclovir works best if it is used within 48 hours after the first symptoms of shingles or genital herpes (e.g., pain, burning, or blisters) begin to appear. For recurrent outbreaks of genital herpes, valacyclovir works best if it is used within 24 hours after the symptoms begin to appear.

If you are taking valacyclovir for the treatment of chickenpox, it is best to start taking valacyclovir as soon as possible after the first sign of the chickenpox rash appears, usually within one day.

Valacyclovir may be taken with meals or on an empty stomach.

If you are using the oral suspension, use a specially marked measuring spoon or other device to measure each dose accurately. The average household teaspoon may not hold the right amount of liquid.

Drink extra fluids so you will pass more urine while you are using this medicine. This will keep your kidneys working well and help prevent kidney problems.

To help clear up your infection, keep taking valacyclovir for the full time of treatment, even if your symptoms begin to clear up after a few days. Do not miss any doses. However, do not use this medicine more often or for a longer time than your doctor ordered.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For oral dosage form (tablets):
    • For treatment of chickenpox:
      • Adults and children below 2 years of age—Use and dose must be determined by your doctor.
      • Children 2 to 18 years of age—Dose is based on body weight and must be determined by your doctor. The usual dose is 20 milligrams (mg) per kilogram (kg) of body weight, taken three times a day for 5 days. However, the dose is usually not more than 1000 mg three times a day.
    • For treatment of cold sores:
      • Adults—2000 milligrams (mg) every 12 hours for one day.
      • Children 12 years of age and above—2000 milligrams (mg) every 12 hours for one day.
      • Children below 12 years of age—Use and dose must be determined by your doctor.
    • For treatment of genital herpes, first outbreak:
      • Adults—1000 milligrams (mg) two times a day for ten days.
      • Children—Use and dose must be determined by your doctor.
    • For treatment of genital herpes, recurrent outbreaks:
      • Adults—500 milligrams (mg) two times a day for three days.
      • Children—Use and dose must be determined by your doctor.
    • To prevent recurrent outbreaks of genital herpes:
      • Adults—500 milligrams (mg) or 1000 mg once a day.
      • Children—Use and dose must be determined by your doctor.
    • For treatment of shingles:
      • Adults—1000 milligrams (mg) three times a day for seven days.
      • Children—Use and dose must be determined by your doctor.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

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Portions of this document last updated: Feb. 01, 2024

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