Valtrex

Generic Name: Valacyclovir

  • What is this medication and its most common uses?

    Valtrex is a medicine used to treat cold sores, genital herpes, and shingles (a painful rash caused by the chickenpox virus) in adults. Valtrex is also used to treat cold sores and chickenpox in children. Valtrex is available as caplets. Your pharmacist can use the caplets to make an oral suspension.

  • What should I know when beginning and continuing on this medication?

    How does this medication work?

    Valtrex works by lowering the ability of the virus to multiply in your body, thereby reducing your symptoms.

    What are the beneficial effects of this medication and when should I begin to have results?

    What:

    Cold Sores: Valtrex has been shown to reduce the duration of cold sore episodes.

    Genital Herpes: In clinical studies, people treated with Valtrex experienced fewer recurrences, and more than half were "recurrence free" at 6 months.

    Shingles: Valtrex has been shown to prevent new blisters from forming.

    Chickenpox: Valtrex has been shown to treat chickenpox in children.

    When: Everyone responds differently to treatment, so try to be patient and follow your healthcare provider's directions. It is important that you take Valtrex exactly as your healthcare provider has prescribed.

    How do I know it is working?

    You may start to notice an improvement in your symptoms after you start taking Valtrex. This is a good indicator that your medication is working. Your healthcare provider may ask you questions and order tests to assess how well your infection is being treated.

  • What are the possible side effects of this medication?

    The following is not a full list of side effects. Side effects cannot be anticipated. If any develop or change in intensity, tell your healthcare provider as soon as possible. Only your healthcare provider can determine if it is safe for you to continue taking this medication.

    Adults

    More common side effects may include: headache, nausea, abdominal (stomach area) pain.

    Children

    More common side effects may include: headache.

    Less common side effects of Valtrex may include:

    Thrombotic thrombocytopenic purpura, a condition in which blood clots form in the blood vessels and can occur all over the body.

    Nervous system problems, with symptoms such as aggressive behavior, unsteady or shaky movements, confusion, speech problems, hallucinations, seizures, or coma.

    Valtrex may also cause severe kidney problems.

  • Who should not take this medication?

    Do not take Valtrex if you are allergic to it, any of its ingredients, or to a similar medicine called acyclovir.

  • What should I tell my healthcare provider before I take the first dose of this medication?

    Tell your healthcare provider about all prescription, over-the-counter, and herbal medications you are taking before beginning treatment with Valtrex. Also, talk to your healthcare provider about your complete medical history, especially if you have kidney problems; advanced HIV disease or autoimmune deficiency syndrome (AIDS); had a bone marrow or kidney transplant; or if you are pregnant, plan to become pregnant, or are breastfeeding.

  • What is the usual dosage?

    The information below is based on the dosage guidelines your healthcare provider uses. Depending on your condition and medical history, your healthcare provider may prescribe a different regimen. Do not change the dosage or stop taking your medication without your healthcare provider's approval.

    Cold Sores

    Adults and adolescents ≥12 years: The recommended dose is 2 grams (g) twice a day (taken 12 hours apart) for 1 day.

    Genital Herpes (Initial Episode)

    Adults: The recommended dose is 1 g twice a day for 10 days.

    Genital Herpes (Recurrent Episodes)

    Adults: The recommended dose is 500 milligrams twice a day for 3 days.

    Genital Herpes (Long-Term Control of Recurrent Episodes)

    Adults: The recommended dose is 1 g once a day. Your healthcare provider may prescribe a different dose, depending on the number of recurrent episodes you experience in a year and your other medical conditions.

    Shingles

    Adults: The recommended dose is 1 g three times a day for 7 days.

    Chickenpox

    Children 2-18 years: Your healthcare provider will prescribe the appropriate dose for your child, based on his/her weight. Your child should take this dose 3 times a day for 5 days.

    If you have kidney impairment, your healthcare provider may adjust your dose appropriately.

  • How should I take this medication?

    Take Valtrex exactly as prescribed by your healthcare provider. Do not change your dose or stop taking Valtrex without first talking to your healthcare provider.

    Take Valtrex with or without food.

    If your child cannot swallow the caplets, your pharmacist may prepare an oral suspension for your child. Shake the suspension well before giving the medicine to your child.

    If you are taking Valtrex to treat cold sores, chickenpox, shingles, or genital herpes, you should start treatment as soon as possible after your symptoms start. Valtrex may not help you if you start treatment too late.

  • What should I avoid while taking this medication?

    Do not have sexual contact with your partner when you have any symptoms or outbreak of genital herpes.

    Do not become dehydrated. Drink adequate amounts of fluids while you are taking Valtrex.

  • What are the possible food and drug interactions associated with this medication?

    No significant interactions have been reported with Valtrex at this time. However, always tell your healthcare provider about any medicines you take, including over-the-counter medications, vitamins, and herbal supplements.

  • May I receive this medication if I am pregnant or breastfeeding?

    The effects of Valtrex during pregnancy are unknown. Valtrex can be found in your breast milk if you take it while breastfeeding. Tell your healthcare provider immediately if you are pregnant, plan to become pregnant, or are breastfeeding.

  • What should I do if I miss a dose of this medication?

    If you miss a dose of Valtrex, take it as soon as you remember. However, if it is almost time for your next dose, skip the one you missed and return to your regular dosing schedule. Do not take two doses at once.

  • How should I store this medication?

    Store Valtrex caplets at room temperature.

    Store Valtrex oral suspension in the refrigerator. Throw away any remaining liquid after 28 days.

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