Pronunciation:

val-ay-SYE-kloe-veer

Brand Names:

• Valtrex

Dosage Forms:

• Tablet

Classifications:

Therapeutic—

Antiviral

Pharmacologic—

Viral DNA Polymerase Inhibitor

Chemical—

Guanosine Nucleoside Analog

Uses of This Medicine:

Valacyclovir is used to treat the symptoms of herpes zoster (also known as shingles), a herpes virus infection of the skin; it is also used to treat and prevent genital herpes infections. In your body, valacyclovir becomes the anti-herpes medicine, acyclovir. Although valacyclovir will not cure shingles or genital herpes, it does help relieve the pain and discomfort and helps the sores heal faster.

Valacyclovir is available only with your doctor's prescription.

Before Using This Medicine:

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies—

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Children—

Studies on this medicine have been done only in adult patients. There is no specific information comparing use of valacyclovir in children with use in other age groups.

Older adults—

Valacyclovir has been used in elderly patients and has not been shown to cause different side effects or problems in older people than it does in younger adults. Elderly patients are at a high risk for dehydration and should drink plenty of fluids.

Pregnancy—

	Pregnancy Category	Explanation
All Trimesters	B	Animal studies have revealed no evidence of harm to the fetus, however, there are no adequate studies in pregnant women OR animal studies have shown an adverse effect, but adequate studies in pregnant women have failed to demonstrate a risk to the fetus.

Breast-feeding—

Studies in women suggest that this medication poses minimal risk to the infant when used during breastfeeding.

Other medicines—

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. Tell your healthcare professional if you are taking any other prescription or nonprescription (over-the-counter [OTC]) medicine.

Other interactions—

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other medical problems—

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

• Advanced human immunodeficiency virus (HIV) infection or
• Bone marrow transplantation or
• Kidney transplantation—Patients with these medical problems may have an increased risk of severe side effects

• Kidney disease—Kidney disease may increase blood levels of this medicine, increasing the chance of side effects

Proper Use of This Medicine:

Valacyclovir works best if it is used within 48 hours after the first symptoms of shingles or genital herpes (for example, 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.

Valacyclovir may be taken with meals.

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 genital herpes, first outbreak:
    • Adults—1 gram 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 mg or 1 gram once a day.
    • Children—Use and dose must be determined by your doctor.
  • For treatment of shingles:
    • Adults—1 gram 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.

Precautions While Using This Medicine:

If your symptoms do not improve within a few days, or if they become worse, check with your doctor.

The areas affected by genital herpes or shingles should be kept as clean and dry as possible. Also, wear loose-fitting clothing to avoid irritating the sores (blisters).

Side Effects of This Medicine:

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

Less common

Painful menstruation, including abdominal cramps, diarrhea, or nausea

Rare

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

Frequency not determined

Back, leg or stomach pains

changes in behavior, especially in interactions with other people

difficulty breathing or swallowing

fast, pounding, or irregular heartbeat

high blood pressure

itching

lightheadedness when getting up from a lying or sitting position

redness of skin

seeing, hearing, or feeling things that are not there

skin rash

swelling or puffiness of face, hands, legs, or feet

wheezing

Symptoms of overdose with intravenous acyclovir

Anxiety

convulsions (seizures)

decrease in urine output

decreased frequency of urination

dry mouth

hallucinations (seeing, hearing, or feeling things that are not there)

irritability

loss of consciousness

lower back/side pain

nervousness

restlessness

Note: Because the information on valacyclovir overdose is limited, information on intravenous acyclovir overdose is provided. In the body, valacyclovir is converted into acyclovir.

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

Headache

nausea

Less common

Constipation

diarrhea

dizziness

joint pain

loss of appetite

stomach pain

unusual tiredness or weakness

vomiting

Frequency not determined

Anxiety

dry mouth

irritability

mood or mental changes

nervousness

restlessness

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.