Generic Name: Valtrex Brand Name(s): Generics only. No brands available.

Uses

What is Valtrex® (valacyclovir) used for?

Valtrex® is an antiviral drug. It slows the growth and spread of the herpes virus to help the body fight the infection.

Valtrex® is used to treat infections caused by herpes viruses, including genital herpes, cold sores, and shingles (herpes zoster) in adults.

Valtrex® is used to treat cold sores in children who are at least 12 years old, or chickenpox in children who are at least 2 years old.

Valtrex® will not cure herpes and will not prevent you from spreading the virus to other people. However, this medicine can lessen the symptoms of an infection.

How should I take Valtrex® (valacyclovir)?

Take Valtrex® exactly as it was prescribed for you. Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended.

Start taking Valtrex® as soon as possible after the first appearance of symptoms (such as tingling, burning, blisters). This medicine might not be as effective if you first start taking it 1 or 2 days after the start of your symptoms.

Some herpes infections need to be treated for longer than others. Use this medicine for the full prescribed length of time. Your symptoms may improve before the infection is completely cleared. Skipping doses may increase the risk of your virus becoming resistant to antiviral medicine.

You may take Valtrex® with or without food.

Drink plenty of water while you are taking Valtrex® to keep your kidneys working properly.

Lesions caused by herpes viruses should be kept as clean and dry as possible. Wearing loose clothing may help to prevent irritation of the lesions.

How do I store Valtrex® (valacyclovir)?

Valtrex® is best stored at room temperature away from direct light and moisture. To prevent drug damage, you should not store Valtrex® in the bathroom or the freezer. There may be different brands of Valtrex® that may have different storage needs. It is important to always check the product package for instructions on storage, or ask your pharmacist. For safety, you should keep all medicines away from children and pets.

You should not flush Valtrex® down the toilet or pour them into a drain unless instructed to do so. It is important to properly discard this product when it is expired or no longer needed. Consult your pharmacist for more details about how to safely discard your product.

Precautions & warnings

What should I know before using Valtrex® (valacyclovir)?

Before using this drug, tell your doctor if:

  • You are pregnant or breastfeeding. This is because, while you are expecting or feeding a baby, you should only take medicines on the recommendation of a doctor.
  • You are taking any other medicines. This includes any medicines you are taking which are available to buy without a prescription, such as herbal and complementary medicines.
  • You have allergy with any of active or inactive ingredients of Valtrex® or other medications.
  • You have any other illnesses, disorders, or medical conditions.
  • You have HIV/AIDS, a weak immune system, kidney disease (or if you are on dialysis), or if you have had a kidney or bone marrow transplant.

Valtrex® can be harmful to the kidneys, and these effects are increased when it is used together with other medicines that can harm the kidneys. Tell your doctor about all other medications you are using. You may need dose adjustments or special tests when taking certain medications together with Valtrex®.

Treatment with Valtrex® should be started as soon as possible after the first appearance of symptoms (such as tingling, burning, blisters).

Is it safe during pregnancy or breastfeeding?

There are no adequate studies in women for determining risk when using Valtrex® during pregnancy or while breastfeeding. Please always consult with your doctor to weigh the potential benefits and risks before taking Valtrex®. Valtrex® is pregnancy risk category B, according to the US Food and Drug Administration (FDA).

FDA pregnancy risk category reference below:

  • A=No risk
  • B=No risk in some studies
  • C=There may be some risk
  • D=Positive evidence of risk
  • X=Contraindicated
  • N=Unknown

Side effects

What side effects can occur from Valtrex® (valacyclovir)?

Get emergency medical help if you have signs of an allergic reaction to Valtrex®: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • Confusion, aggression, or you feel shaky or unsteady
  • Hallucinations (seeing or hearing things that are not real)
  • Problems with speech
  • A seizure (convulsions)
  • Kidney problems–little or no urination, painful or difficult urination, swelling in your feet or ankles, feeling tired or short of breath

Stop taking Valtrex® and call your doctor right away if you have any of the following signs of a serious side effect that can harm red blood cells:

  • Fever, pale skin
  • Unusual bleeding (nosebleeds, bleeding gums)
  • Red or pink urine, little or no urination
  • Red spots on the skin (not related to herpes or chickenpox)
  • Feeling weak or tired
  • Stomach pain, bloody diarrhea, vomiting
  • Swelling of your face, hands, or feet

Side effects may be more likely in adults who are 65 or older.

Common Valtrex® side effects may include:

  • Nausea, stomach pain
  • Headache
  • Rash
  • Tired feeling

Not everyone experiences these side effects. There may be some side effects not listed above. If you have any concerns about a side-effect, please consult your doctor or pharmacist.

Interactions

What drugs may interact with Valtrex® (valacyclovir)?

Valtrex® may interact with other drugs that you are currently taking, which can change how your drug works or increase your risk for serious side effects. To avoid any potential drug interactions, you should keep a list of all the drugs you are using (including prescription drugs, nonprescription drugs, and herbal products) and share it with your doctor and pharmacist. For your safety, do not start, stop, or change the dosage of any drugs without your doctor’s approval.

Does food or alcohol interact with Valtrex® (valacyclovir)?

Valtrex® may interact with food or alcohol by altering the way the drug works or increase the risk for serious side effects. Please discuss with your doctor or pharmacist any potential food or alcohol interactions before using this drug.

What health conditions may interact with Valtrex® (valacyclovir)?

Valtrex® may interact with your health condition. This interaction may worsen your health condition or alter the way the drug works. It is important to always let your doctor and pharmacist know all the health conditions you currently have.

Health conditions that may interact with this drug are:

  • Kidney disease (or if you are on dialysis)
  • HIV/AIDS, or other conditions that can weaken the immune system
  • A history of kidney transplant or bone marrow transplant

Dosage

The information provided is not a substitute for any medical advice. You should ALWAYS consult with your doctor or pharmacist before using Valtrex® (valacyclovir).

What is the dose of Valtrex® (valacyclovir) for an adult?

Usual Adult Dose for Herpes Simplex Labialis:

2 g orally every 12 hours for a total of 2 doses (4 g)

Therapy should be started at the earliest sign of a cold sore (such as tingling, burning, or itching).

Usual Adult Dose for Herpes Simplex — Mucocutaneous/Immunocompetent Host:

Genital herpes: First episode: 1 g orally twice a day for 7 to 10 days

The efficacy has not been established if started more than 72 hours after onset of signs and symptoms.

Recurrent episode: 500 mg orally twice a day for 3 days

Therapy should be started at the first sign of a genital herpes episode. The efficacy has not been established if started more than 24 hours after onset of signs and symptoms.

Usual Adult Dose for Herpes Simplex — Suppression:

Chronic suppression of recurrent genital herpes:

Immunocompetent host: 1 g orally once a day

Alternative dose for immunocompetent host with a history of 9 or fewer recurrences per year: 500 mg orally once a day

Safety and efficacy beyond 1 year have not been established in immunocompetent patients.

HIV-infected host with CD4 count 100 cells/mm3 or more: 500 mg orally twice a day

Safety and efficacy beyond 6 months have not been established in HIV-infected patients.

Reduction of transmission of genital herpes in immunocompetent host with a history of 9 or fewer recurrences per year: 500 mg orally once a day for the source partner

Efficacy beyond 8 months has not been established in discordant couples.

Usual Adult Dose for Herpes Zoster:

1 g orally every 8 hours for 7 days

Most effective if started within 48 hours of onset of rash. The efficacy has not been established if started more than 72 hours after onset of rash.

Usual Adult Dose for Herpes Simplex — Mucocutaneous/Immunocompromised Host:

Genital herpes in HIV-infected host:

First episode: 1 g orally twice a day for 7 to 14 days

The efficacy has not been established if started more than 72 hours after onset of signs and symptoms.

Recurrent episode: 1 g orally twice a day for 5 to 14 days

Therapy should be started at the first sign of a genital herpes episode. The efficacy has not been established if started more than 24 hours after onset of signs and symptoms.

The use of Valtrex for the treatment of initial and recurrent genital herpes in HIV-infected patients is not approved by the FDA.

Usual Adult Dose for CMV Prophylaxis:

In renal transplant recipient: 2 g orally 4 times a day

The use of Valtrex for cytomegalovirus prophylaxis is not approved by the FDA.

What is the dose of Valtrex® (valacyclovir) for a child?

Usual Pediatric Dose for Herpes Simplex Labialis:

12 years or older: 2 g orally every 12 hours for a total of 2 doses (4 g)

Therapy should be started at the earliest sign of a cold sore (such as tingling, burning, or itching).

Usual Pediatric Dose for Varicella-Zoster:

Chickenpox in immunocompetent host:

2 to less than 18 years: 20 mg/kg orally 3 times a day for 5 days

Maximum dosage: 1 g orally 3 times a day

Therapy should be initiated at the earliest sign of chickenpox, no later than 24 hours after onset of rash.

How is Valtrex® (valacyclovir) available?

Valtrex® (valacyclovir) is available in the following dosage forms and strengths:

  • Tablet, film coated: valacyclovir hydrochloride 500mg

What should I do in case of an emergency or overdose?

In case of an emergency or an overdose, call your local emergency services or go to your nearest emergency room.

What should I do if I miss a dose?

If you miss a dose of Valtrex®, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and take your regular dose as scheduled. Do not take a double dose.

Hello Health Group does not provide medical advice, diagnosis or treatment.

Sources

Review Date: September 2, 2017 | Last Modified: September 2, 2017

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