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Valacyclovir Pregnancy and Breastfeeding Warnings

Valacyclovir is also known as: Valtrex

Valacyclovir Pregnancy Warnings

Benefit should outweigh risk

AU TGA pregnancy category: B3
US FDA pregnancy category: B

Comments:
-Acyclovir (aciclovir) has been safely used to treat genital herpes in women in all stages of pregnancy; data on prenatal exposure to this prodrug is limited, however, animal data suggests low risk.
-Women who acquire genital herpes simplex virus (HSV) during late pregnancy should be managed in consultation with maternal-fetal medicine and infectious-disease specialists.
-Suppressive therapy late in pregnancy has been shown to reduce the frequency of cesarean delivery among women with recurrent genital herpes by diminishing the frequency of recurrences at term; such treatment may not protect against transmission to neonates in all cases.
-Recommended regimen for HSV suppressive therapy in pregnant women with recurrent genital herpes: 500 mg orally 2 times a day starting at 36 weeks gestation.

Animal studies have failed to reveal evidence of teratogenicity for either valacyclovir (valaciclovir) or acyclovir (aciclovir; the active metabolite). There are no controlled data in human pregnancy. No significant neonatal toxicity or fetal drug accumulation was noted in a small pharmacokinetic study (n=20) of this drug (500 mg twice daily) administered beginning at 36 weeks' gestation. Pregnancy registry data reported 111 and 1246 document exposures to this drug or any formulation of its active metabolite, respectively, of which 29 and 756 exposures occurred in the first trimester. Exposure did not indicate an increased incidence of major birth defects compared with the general population in a prospective pregnancy registry; however, there is insufficient data for definitive conclusions regarding exposure during pregnancy.

AU TGA pregnancy category B3: Drugs which have been taken by only a limited number of pregnant women and women of childbearing age, without an increase in the frequency of malformation or other direct or indirect harmful effects on the human fetus having been observed. Studies in animals have shown evidence of an increased occurrence of fetal damage, the significance of which is considered uncertain in humans.

US FDA pregnancy category B: Animal reproduction studies have failed to demonstrate a risk to the fetus and there are no adequate and well-controlled studies in pregnant women.

See references

Valacyclovir Breastfeeding Warnings

This drug is a prodrug that is convert rapidly to acyclovir (acyclovir). Following maternal ingestion, it is found in the breast milk as acyclovir (aciclovir) in concentrations that at less than 1% to 2% of a typical infant dose. In 5 nursing mothers and infant pairs, this prodrug was not detected in maternal serum, breast milk, or infant urine following maternal doses of 500 mg twice a day. The expected acyclovir (acyclovir) dose was calculated at approximately 0.6 mg/kg/day

Use with caution

Excreted into human milk: Yes

Comments: Based on its rapid conversion to acyclovir (acyclovir), this drug appears to be compatible with breastfeeding.

See references

References for pregnancy information

  1. CDC. Centers for Disease Control and Prevention "Sexually Transmitted Diseases Treatment Guidelines, 2015. Available from: URL: http://www.cdc.gov/std/tg2015/default.htm." (June 5, 2015):
  2. Cerner Multum, Inc. "Australian Product Information." O 0
  3. "Product Information. Valtrex (valacyclovir)." Glaxo Wellcome, Research Triangle Park, NC.
  4. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

References for breastfeeding information

  1. Department of Adolescent and Child Health and Development. UNICEF. World Health Organization "Breastfeeding and maternal medication: recommendations for drugs in the eleventh Who model list of essential drugs. Available from: URL: http://whqlibdoc.who.int/hq/2002/55732.pdf?ua=1" ([2003]):
  2. CDC. Centers for Disease Control and Prevention "Sexually Transmitted Diseases Treatment Guidelines, 2015. Available from: URL: http://www.cdc.gov/std/tg2015/default.htm." (June 5, 2015):
  3. Cerner Multum, Inc. "Australian Product Information." O 0
  4. "Product Information. Valtrex (valacyclovir)." Glaxo Wellcome, Research Triangle Park, NC.
  5. United States National Library of Medicine "Toxnet. Toxicology Data Network. Available from: URL: http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT." ([cited 2013 -]):

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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