What is Valtrex?
Valtrex is a brand of valacyclovir, a medication used to treat infections caused by certain types of viruses. These infections include oral and genital herpes, shingles, and chickenpox.
• Oral herpes causes cold sores. These are small, painful sores that you can get in or around your mouth. Cold sores can be spread by kissing or other physical contacts with the infected area of the skin.
• Genital herpes is a sexually transmitted disease. This means it’s spread through sexual contact. Symptoms include small, painful blisters on the genital area. You can spread genital herpes to your sexual partner even when you don’t have any symptoms. This drug is used to treat or prevent flare-ups of genital herpes in people with normal immune systems, or in people with HIV.
• Shingles are caused by the same virus that causes chickenpox (varicella zoster). Symptoms of shingles include small, painful blisters that appear on the skin. Shingles can occur in people who have already had chickenpox. It can also spread to people who have not had chickenpox before through contact with the infected skin.
• Chickenpox causes an itchy rash of small, red bumps that can look like pimples or insect bites. The rash can spread almost anywhere on the body. Chickenpox can also cause flu-like symptoms, such as fever or tiredness. This drug is used to treat chickenpox in children ages 2 to18 years who have a normal immune system.
How it works
Valtrex 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. Valtrex decreases the severity and length of these outbreaks. It helps the sores heal faster, keeps new sores from forming, and decreases pain and itching. This medication may also help reduce how long pain remains after the sores heal.
How should I take Valtrex?
Valtrex comes as a tablet to take by mouth. It is usually taken every 8 hours (three times a day) for 7 days to treat shingles. To treat genital herpes, it is usually taken twice a day for 5 days.
The typical dosing for Valtrex is as follows:
Adults
Cold sores: Take 2 grams by mouth every 12 hours for 1 day.
Genital herpes (the first outbreak): Take 1 gram by mouth twice daily for 10 days.
Genital herpes (recurrent outbreaks): Take 500 mg by mouth twice daily for 3 days.
Genital herpes (reduction of recurrent outbreaks): Take 500 mg to 1 gram by mouth once daily. For people who also have HIV, the dose would be 500 mg by mouth twice daily.
Genital herpes (reduction of transmission): Take 500 mg by mouth once daily.
Shingles: Take 1 gram by mouth three times daily for 7 days.
Children
Cold sores (age 12 or older): Take 2 grams by mouth every 12 hours for 1 day.
Chickenpox (ages 2 to 17): Dose is based on weight. The typical dose is 20 mg/kg by mouth three times daily for 5 days, with a maximum of 1 gram by mouth three times daily.
Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take valacyclovir exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor. Use this medication as soon as possible after symptoms appear.
Continue to take Valtrex even if you feel well. Do not stop taking valacyclovir without talking to your doctor.
Pros And Cons Of Taking Valtrex Daily
Some conditions may require that you take Valtrex daily, doing so comes with some benefits and side effects.
Pros
- Taking 500 mg to 1 gram of Valtrex by mouth once daily appears to have benefits for managing symptoms and reducing recurrent episodes.
- Taking Valtrex daily helps prevent resistance as skipping doses may increase the risk of your virus becoming resistant to antiviral medicine.
- Taking Valtrex daily may help lower the risk of spreading this disease to your sexual partner.
- An additional benefit of the daily dose of Valtrex is that can be taken as a divided dose.
- Taking Valtrex daily prevents flare-ups in people with a normal immune system and immunocompromized persons with people with HIV.
Cons
- Valtrex cannot be used in infants and children younger than 12 as the drug has not been studied or approved for the treatment of oral herpes in children younger than 12 years. This drug has also not been studied or approved for the treatment of shingles in children younger than 18 years.
- Valtrex can cause your body to process drugs more slowly especially if you are older. As a result, a higher amount of a drug stays in your body for a longer time. This raises your risk of side effects.
- People prone to an allergic reaction can not take the medication especially if they have ever had an allergic reaction to it. Taking it again could be fatal (cause death).
- Valtrex has been reported to cause nervous system problems including agitation, hallucinations, confusion, aggressive behavior, seizures, and speech problems.
What side effects can Valtrex cause?
Valtrex may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- constipation
- diarrhea or loose stools
- headache
- upset stomach
- vomiting
If you experience any of the following side effects, call your doctor immediately:
- blood in the urine
- confusion
- fever
- itching
- rash
- yellowness of the skin or eyes
If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration’s (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).
Valtrex interactions
There may be interactions between Valtrex and the following medications:
• cladribine
• clozapine
• foscarnet
• mycophenolate
• tenofovir
• theophyllines (e.g., aminophylline, oxtriphylline, theophylline)
• tizanidine
• varicella virus vaccine
• zidovudine
• zoster vaccine
If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:
• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.
An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.
