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- What is Valtrex (valacyclovir)? What are its uses?
- What are the side effects of Valtrex (valacyclovir)?
- What is the dosage for Valtrex (valacyclovir)?
- Which drugs or supplements interact with Valtrex (valacyclovir)?
- Is Valtrex (valacyclovir) safe to use during pregnancy or while breastfeeding?
- How does Valtrex (valacyclovir) work (mechanism of action)?
- What else should I know about Valtrex (valacyclovir)?
What are the side effects of Valtrex (valacyclovir)?
Common side effects are:
- Abdominal pain
- Cold symptoms
- Increased liver enzymes
- Reduction of white blood cells
Other important side effects are:
More serious side effects include central nervous system side effects which are more likely to happen in the elderly, for example:
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What is the dosage for Valtrex (valacyclovir)?
- Valtrex may be taken with or without food.
- In people with kidney disease, doses need to be reduced.
- For the treatment of herpes zoster (shingles), the usual dose is 1 gm. three times a day for 7 days. Treatment should begin at the first symptom and is most effective if started within 48 hours of the onset of rash.
- The dose for chickenpox is 20 mg/kg 3 times daily for 5 days (maximum dose is 1000 mg 3 times daily) and treatment should start at the earliest sign or symptom.
- For the treatment of an initial episode of genital herpes, the usual dose is 1 gram (1000 mg) twice daily for 10 days. For the treatment of recurrent genital herpes, the usual dose is 500 mg twice daily for 3 days. For best results, treatment should be initiated within 12 hours of the start of symptoms.
- The dose for cold sores is 2000 mg (2 grams) every 12 hours for 1 day.
Which drugs or supplements interact with Valtrex (valacyclovir)?
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Is Valtrex (valacyclovir) safe to use during pregnancy or while breastfeeding?
- Valtrex showed no effects on the fetus in animal studies; however, there has been no adequate evaluation of valacyclovir or (acyclovir) in pregnant women. The incidence of birth defects in women taking acyclovir is about the same as in the general population. Valtrex should only be used during pregnancy when the benefits to the mother outweigh risks to the fetus.
- It is not known whether Valtrex is excreted into breast milk. It is known, however, that among women taking acyclovir, concentrations of acyclovir in breast milk are about four times higher than in the mother's blood. The safety of valacyclovir in breastfeeding infants has not been established. Methods other than breastfeeding should be considered if valacyclovir must be taken while nursing.
How does Valtrex (valacyclovir) work (mechanism of action)?
Valtrex belongs to a class of drugs called nucleoside analogs that mimic one of the building blocks of DNA. It stops the spread of herpes virus in the body by preventing the replication of viral DNA that is necessary for viruses to multiply. Other drugs in the same class include acyclovir (Zovirax) and famciclovir (Famvir). Valacyclovir is actually a "prodrug," in that it is not active itself. Rather, it is converted to acyclovirin the body, and it is the acyclovir that is active against the viruses. (Acyclovir itself is available as a topical, oral and intravenous medication.) Valacyclovir, therefore, is active against the same viruses as acyclovir, but valacyclovir has a longer duration of action than acyclovir, and, therefore, can be taken fewer times each day.
The FDA approved valacyclovir in 1995.
What else should I know about Valtrex (valacyclovir)?
- Valacyclovir) is available as tablets of 500 and 1000 mg
- Valtrex should be kept stored between 2 C and 30 C (36 F and 86 F).
- Valacyclovir is available in generic form. You need a prescription from your doctor for it.
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Valtrex (valacyclovir) is an antiviral drug prescribed for the treatment of herpes viruses such as shingles, genital herpes, and cold sores. Side effects include abdominal pain, diarrhea, dizziness, nausea, vomiting, and headache. Drug interactions, warnings and precautions, and pregnancy and breastfeeding safety information should be reviewed prior to taking any medication.
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Related Disease Conditions
Shingles, or herpes zoster, is a painful rash caused by the varicella zoster virus. Other shingles symptoms include headache, fever, nausea, and body aches. Treatment focuses on pain management and shortening the duration of the illness with antiviral medications.
STDs in Men
Sexually transmitted diseases (STDs) are infections transmitted during sexual contact. They may be caused by viruses, bacteria, or parasites. STDs in men cause no symptoms or symptoms like genital burning, itching, sores, rashes, or discharge. Common infections that are sexually transmitted in men include gonorrhea, chlamydia, syphilis, hepatitis C and B, genital warts, human papillomavirus (HPV), and genital herpes. Some STDs in men are treatable while others are not. STDs are diagnosed with tests that identify proteins or genetic material of the organisms causing the infection. The prognosis of an STD depends on whether the infection is treatable or not. Use of latex condoms can help reduce the risk of contracting an STD but it does not eliminate the risk entirely.
Cold Sores (Nongenital Herpes Simplex Infections)
Herpes simplex infections are common and when they appear around the mouth and lips, people often refer to them as "cold sores" and "fever blisters." Canker sores are different than cold sores. Air droplets can spread the virus, as can direct contact with the fluid from the blisters. Cold sore treatment include over-the-counter medication, as well as prescription medications.
Is Shingles Contagious?
Shingles is an infection caused by the varicella-zoster virus. Shingles symptoms and signs include skin burning, numbness, and tingling along with a painful red, blistering rash. Shingles is contagious until all of the blisters have crusted over.
Sexually Transmitted Diseases in Women (STDs)
Sexually transmitted diseases (STDs) are among the most common infectious diseases in the United States. STDs can be spread through any type of sexual activity involving the sex organs, the anus or mouth, or through contact with blood during sexual activity. Examples of STDs include, chancroid, chlamydia, gonorrhea, granuloma inguinale, lymphogranuloma venereum, syphilis, genital herpes, genital warts, trichomoniasis, pubic lice (crabs), and scabies. Treatment is generally with antibiotics; however, some STDs that go untreated can lead to death.
Genital Herpes in Women (Symptoms, Signs, Treatment)
Genital herpes is a sexually transmitted disease (STD) caused by the herpes simplex virus (HSV). Symptoms of genital herpes include painful blisters and often fever, body aches, and swollen lymph nodes for first time infection. Genital herpes is diagnosed with lab tests to test for the presence of the virus. Treatment for genital herpes includes antiviral medications to shorten the duration of the outbreak or reduce the risk of future outbreaks. There is no cure for genital herpes. Condoms may help prevent the spread of genital herpes.
Pimple vs. Cold Sore
Pimples are areas of skin inflammation with pus in the center. Cold sores are fluid-filled blisters. Pimples are caused by bacterial overgrowth and inflammation. Cold sores are caused by infection with herpes simplex viruses (HSV-1 and HSV-2). Benzoyl peroxide and sometimes antibiotics treat acne. Antiviral medications accelerate the healing process of oral herpes.
Chickenpox (chicken pox) is a contagious childhood disease caused by the varicella-zoster virus. Symptoms have an incubation period of 14 to 16 days and include a couple days of mild fever, weakness, and red, raised rash that progresses to blisters that eventually burst and crust over. Complications include bacterial infection of the open sores, scarring, encephalitis, nerve palsies, and Reye's syndrome.
What Happens When You Get Shingles When Pregnant?
Becoming infected with chickenpox during pregnancy could cause birth defects in your unborn child. Likewise, shingles could also cause problems for your unborn child. If you are pregnant and haven't had chickenpox, avoid exposure to infected people. Zostavax, the shingles vaccine, can reduce the incidence of shingles by half. Women should wait at least three months after receiving the vaccine before trying to get pregnant.
Are Cold Sores (Fever Blisters) Contagious?
About 20% of cases of cold sores are caused by herpes simplex virus type 2 (HSV-2), and approximately 80% of cold sores are caused by herpes simplex virus type 1 (HSV-1). Cold sores are transmitted by sharing utensils and razors, kissing, and oral sex. There is no cure for cold sores.
Is Chickenpox Contagious?
Chickenpox is an infectious disease caused by the varicella zoster virus. Chickenpox symptoms and signs include a blistering, itchy rash, fatigue, fever, and tiredness. Chickenpox is transmitted via contaminated droplets produced during sneezing or coughing and by coming in contact with blister fluid.
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Sexually Transmitted Diseases and Pregnancy (STDs)
When you are pregnant, many sexually transmitted diseases (STDs) can be especially harmful to you and your baby. These STDs include herpes, HIV/AIDS, genital warts (HPV), hepatitis B, chlamydia, syphilis, gonorrhea, and trichomoniasis. Symptoms include bumps, sores, warts, swelling, itching, or redness in the genital region. Treatment of STDs while pregnant depends on how far along you are in the pregnancy and the progression of the infection.
Sexual health information including birth control, impotence, herpes, sexually transmitted diseases, staying healthy, women's sexual health concerns, and men's sexual health concerns. Learn about the most common sexual conditions affecting men and women.
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