Important Facts About Using Valtrex During Pregnancy


Valtrex and pregnancy may not be a good combination for a developing fetus. Read on to find out more about this common herpes drug.

Information on Valtrex and Pregnancy

Valtrex is a prescription medication taken to lower the ability of herpes viruses to increase in the body. Valtrex is taken to treat the following symptoms:

  • Cold sores
  • Shingles
  • Treat and/or control genital herpes in adults
  • Control genital herpes outbreaks in certain adults with HIV

Valtrex is also taken to help prevent the spread of genital herpes to other adults. It should be used along with safe sex practices. Valtrex is only a treatment for these health issues, not a cure.

If you have genital herpes and plan to get pregnant, you should speak to your doctor. Genital herpes can be passed onto your baby in a condition called neonatal herpes. But if you are infected early in pregnancy or before becoming pregnant, chances are less than one percent that you will pass the virus to your baby. Speak with your doctor for more information.

The active ingredient in Valtrex is valacyclovir hydrochloride (acyclovir). This ingredient has not been extensively studied for use in pregnant women.

A registry was started in 1984 and completed in 1999 for use in pregnant women. The occurrence of birth defects approximated that of the general population. However, less than 800 women participated in the study. This makes it too small to draw conclusions for less common birth defects or to produce accurate findings for safety of mom and the developing fetus if taken during pregnancy.

Studies done on rats and rabbits found that valacylovir did not cause developmental malformations during the period of major body organ development. These studies were reported by GlaxoSmithKline, the maker of Valtrex.

Valtrex and pregnancy use should be evaluated and monitored by a doctor. Valtrex has been rated by the Food and Drug Administration as a pregnancy category "B"--meaning it is not expected to cause harmful effects to a fetus. However, you should not take Valtrex when pregnant unless under a physician's care.

If you need to take Valtrex and have a doctor's permission, but cannot afford the medicine, options are available. Visit GSK for You to learn more about savings programs to help you get the drugs you need.

Valtrex and the Nursing Mom

If you plan to breastfeed your baby, you should only take Valtrex under the advisement of a doctor and when indicated.

A study reported by GlaxoSmithKline shows that ingredients in Valtrex can be passed onto a baby through breastmilk. When 500mg dosages of Valtrex were given twice a day to a nursing mom, a portion of acyclovir of approximately .6 mg/kg/day were passed onto the baby.

More Information on Prescription Drugs

Before taking any medicine, whether over-the-counter or prescription, you should always consult with your doctor. Learning about the possible side effects for both you and your developing baby can help you make a more informed decision about the consequences of taking the drug.

More information on drugs and their effects on pregnancy can be found at:

Important Facts About Using Valtrex During Pregnancy