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

Uses

What is valacyclovir used for?

Valacyclovir is commonly used for treating infections caused by certain types of viruses. In children, it is used to treat cold sores around the mouth (caused by herpes simplex) and chickenpox (caused by varicella zoster) in children who are at least 12. In adults, it is used to treat shingles (caused by herpes zoster) and cold sores around the mouth.

Valacyclovir is also used to treat outbreaks of genital herpes. In people with frequent outbreaks, this medication is used to reduce the number of future episodes.

Valacyclovir stops the growth of certain viruses. However, it is not a cure for these infections. The viruses that cause these infections continue to live in the body even between outbreaks. Valacyclovir decreases the severity and length of these outbreaks. It helps the sores heal faster, keeps new sores from forming, and decreases pain/itching.

How should I take valacyclovir?

Take valacyclovir by mouth, with or without food, as directed by your doctor. Drink plenty of fluids while taking this medication to lower the chance of side effects.

This medication works best when started at the first sign of an outbreak, as directed by your doctor. It may not work as well if you delay treatment. For shingles or chickenpox, start taking valacyclovir at the first symptom or as soon as possible after the rash appears. For cold sores or genital herpes, start taking this medication at the first sign or as soon as you feel tingling, itching, or burning.

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.

Valacyclovir works best when the amount of medicine in your body is kept at a constant level. Therefore, take this drug at evenly spaced intervals.

How do I store valacyclovir?

Valacyclovir is best stored at room temperature away from direct light and moisture. To prevent drug damage, you should not store valacyclovir in the bathroom or the freezer. There may be different brands of valacyclovir 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 valacyclovir 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 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 valacyclovir 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.

Is it safe during pregnancy or breastfeeding?

There are no adequate studies in women for determining risk when using this medication during pregnancy or while breastfeeding. Please always consult with your doctor to weigh the potential benefits and risks before taking this medication. This medication 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 valacyclovir?

Get emergency medical help if you have signs of an allergic reaction to valacyclovir: 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

Common valacyclovir side effects may include:

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

Stop taking valacyclovir and call your doctor immediately 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 in your face, hands, or feet

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 valacyclovir?

Valacyclovir 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.

Products that may interact with this drug are other drugs that may cause kidney problems (including nonsteroidal anti-inflammatory drugs-NSAIDs such as ibuprofen, naproxen).

Does food or alcohol interact with valacyclovir?

Valacyclovir 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 valacyclovir?

Valacyclovir 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:

  • Renal Impairment
  • Ttp/Hus
  • Hemodialysis

Dosage

The information provided is not a substitute for any medical advice. You should ALWAYS consult with your doctor or pharmacist before using this medication.

What is the dose of valacyclovir for an adult?

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).

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.

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.

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.

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

For CMV Prophylaxis:

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

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

What is the dose of valacyclovir for a child?

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).

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 valacyclovir available?

Valacyclovir is available in the following strengths:

  • Tablet 500 mg; 1 g

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 valacyclovir, 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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