- Bacterial Infections 101 Pictures Slideshow
- Take the Tummy Trouble Quiz
- Hepatitis C Slideshow Pictures
- Valtrex (valacyclovir) vs. Abreva (docosanol): What's the difference?
- What is Valtrex? What is Abreva?
- What are the side effects of Valtrex and Abreva?
- What is the dosage of Valtrex vs. Abreva?
- What drugs interact with Valtrex and Abreva?
- Are Valtrex and Abreva safe to use while pregnant or breastfeeding?
Valtrex (valacyclovir) vs. Abreva (docosanol): What's the difference?
- Valtrex (valacyclovir) and Abreva (docosanol) are antiviral drugs used to treat cold sores (herpes labialis).
- Valtrex is also used to treat shingles (herpes zoster) and genital herpes (herpes simplex genitalis) infections.
- Abreva is available over-the-counter (OTC) and as a generic.
- Valtrex is an oral drug and Abreva is a topical (for the skin) medication.
- Side effects of Valtrex that are different from Abreva include headache, nausea, vomiting, abdominal pain, cold symptoms, increased liver enzymes, reduction of white blood cells, diarrhea, rash, joint pain, and dizziness.
- Side effects of Abreva that are different from Valtrex include application site redness or swelling.
What is Valtrex? What is Abreva?
Valtrex (valacyclovir) is an antiviral drug used to treat shingles (herpes zoster) and genital herpes (herpes simplex genitalis) infections, and cold sores (herpes labialis). Valtrex is a nucleoside analog that mimics 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 nucleoside analogs include acyclovir (Zovirax) and famciclovir (Famvir). Valacyclovir is actually a "prodrug," in that it is not active itself. Rather, it is converted to acyclovir in 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 thus is active against the same viruses as acyclovir, but valacyclovir has a longer duration of action than acyclovir and can be taken fewer times each day.
Abreva (docosanol) is used to treat "cold sores/fever blisters" (herpes labialis). It can speed up healing of the sores and decrease symptoms (such as tingling, pain, burning, itching). It works by blocking the virus that causes the cold sores (herpes simplex) from entering the healthy skin cells and growing in number. Abreva does not cure herpes and does not prevent passing the infection to someone else. It does not prevent a future occurrence. Abreva is not used to treat canker sores (sores found commonly in the mouth), shingles, or genital herpes.
What are the side effects of Valtrex and Abreva?
The side effect profile of Valtrex is similar to that of acyclovir (Zovirax).
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:
- Increased heart rate (tachycardia)
- Encephalopathy (a disorder of the brain)
- Decreased number of blood platelets
- Increased heart rate
- High blood pressure (hypertension)
Side effects of Abreva are uncommon and may include:
- Skin itching
- Redness where the medicine is applied
Latest Infectious Disease News
Daily Health News
What is the dosage of Valtrex vs. Abreva?
- 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 gram 3 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.
Adults and children 12 years or over:
- Wash hands before and after applying cream.
- Apply to affected area on face or lips at the first sign of cold sore/fever blister (tingle).
- Early treatment ensures the best results.
- Rub in gently but completely.
- Use 5 times a day until healed.
Children under 12 years:
- Ask a doctor.
What drugs interact with Valtrex and Abreva?
No information provided.
Are Valtrex and Abreva safe to use while pregnant or 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.
There is no information about Abreva and pregnancy or breastfeeding safety.
Subscribe to MedicineNet's General Health Newsletter
Valtrex and Abreva are antiviral drugs used to treat cold sores (herpes labialis). Valtrex is also used to treat shingles (herpes zoster) and genital herpes (herpes simplex genitalis) infections. Abreva is a topical (for the skin) medication available over-the-counter (OTC) and as a generic. Valtrex is an oral drug.
Multimedia: Slideshows, Images & Quizzes
Shingles Rash Pictures, Symptoms, Vaccine Facts
Is shingles contagious? Shingles (herpes zoster virus) is a painful, contagious rash caused by the Varicella zoster virus. Learn...
Shingles Quiz: Symptoms, Vaccine & Pictures
Shingles falls within a well-known family of viruses that cause itching, burning, blisters, and pain. Take the Shingles Quiz to...
Genital Herpes Quiz: What is Genital Herpes?
What is genital herpes? Learn the causes, symptoms in men and women, and treatments for this common sexually transmitted skin...
Picture of Shingles
An acute infection caused by the herpes zoster virus, the same virus as causes chickenpox. See a picture of Shingles and learn...
Picture of Herpes Zoster
Also called shingles, zona, and zoster. The culprit is the varicella-zoster virus. Primary infection with this virus causes...
Picture of Herpes Blister (Cold Sore)
Cold sores (fever blisters) are caused by the herpes simplex virus (HSV), passed on through contact with infected skin or body...
Picture of Herpes Simplex Virus Type 1
A herpes virus that causes cold sores and fever blisters in and around the mouth. See a picture of Herpes Simplex Virus Type 1...
Picture of Herpes Simplex Virus Type 2
A herpes virus that causes genital herpes, which is characterized by sores in the genital area. See a picture of Herpes Simplex...
Shingles: Myths and Facts About the Shingles Virus
There are some common misconceptions about this viral illness and the uncomfortable rash it can cause. Here's a guide through the...
Genital Herpes: Causes, Treatment, and Prevention
What's going on down there? WebMD shows you pictures of genital herpes symptoms and treatments -- and how to avoid getting the...
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.
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.
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.
Shingles and Pregnancy
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.
Treatment & Diagnosis
- Shingles (Herpes Zoster) FAQs
- Genital Herpes FAQs
- Shingles Pain
- Is Herpes During Pregnancy Dangerous to the Baby?
- Shingles Contagious Period and Diagnosis
- Shingles Prevention: Who Should Get the Vaccine?
- Shingles During Pregnancy
- Shingles Treatment
- Cold Sore Treatment
- Shingles Symptoms and Signs
- Genital Herpes Treatment
- Genital Herpes Symptoms and Signs
- Shingles Causes
Medications & Supplements
Prevention & Wellness
Infectious Disease Resources
Health Solutions From Our Sponsors
Health Solutions From Our Sponsors
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.