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Ritonavir Pregnancy and Breastfeeding Warnings

Ritonavir is also known as: Norvir, Norvir Soft Gelatin

Ritonavir Pregnancy Warnings

This drug should be used during pregnancy only if clearly needed and the benefit outweighs the risk to the fetus. AU TGA pregnancy category: B3 US FDA pregnancy category: B Comments: -A pregnancy exposure registry is available. -The oral solution contains 43.2% (v/v) alcohol and may not be suitable for pregnant women.

Animal studies have failed to reveal evidence of treatment-related malformation; developmental toxicity was observed in rats (early resorption, decreased fetal body weight, ossification delays, developmental variations) and rabbits (resorptions, decreased litter size, decreased fetal weights) at maternally toxic doses. In humans, lower plasma drug levels have been observed during pregnancy compared to postpartum. Placental transfer to the fetus has been reported as low (cord blood/maternal delivery plasma drug ratio less than 0.3). There are no controlled data in human pregnancy. According to some experts, this drug should be used during pregnancy only as a low-dose booster to increase plasma levels of other protease inhibitors. To monitor maternal-fetal outcomes of pregnant women exposed to antiretroviral therapy, an Antiretroviral Pregnancy Registry (APR) has been established. Healthcare providers are encouraged to prospectively register patients. For additional information: The APR has received prospective reports of over 5900 exposures to ritonavir-containing regimens (over 2700 exposed in the first trimester; over 3200 exposed in the second/third trimester) resulting in live births. Enough first trimester exposures have been monitored to detect at least a 1.5-fold increase in risk of overall birth defects and a 2-fold increase in risk of birth defects in the cardiovascular and genitourinary systems; no such increases detected. There was no difference between ritonavir and overall birth defects compared with the background birth defect rate of 2.7% in the reference population. The prevalence of defects in the first trimester was 2.3% for ritonavir; in the second/third trimester, the prevalence of defects was 2.9%. 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

Ritonavir Breastfeeding Warnings

In 1 study, nursing mothers used this drug as part of a clinical trial to evaluate maternal-to-child transmission of HIV infection. Doses, dose regimens, and breast milk collection times were not provided. This drug was not detected in any of 60 breast milk samples. A total of 23 milk samples were obtained (at birth, 1 month, 3 months, and/or 6 months postpartum) from 9 mothers using lopinavir 400 mg plus ritonavir 100 mg twice a day as part of combination antiretroviral therapy. Their breastfed infants had a total of 6 blood samples analyzed at 1 month, 3 months, and/or 6 months postpartum. Milk samples and infant blood samples were collected at about 4.5 hours (range: 3.5 to 6 hours) after the previous maternal dose and about 30 minutes (range: 20 to 60 minutes) after nursing. The ritonavir level in breast milk averaged 79 mcg/L (range: 31 to 193 mcg/L); the ritonavir plasma level in infants averaged 7 mcg/L (range: 0 to 138 mcg/L), which was about 12% (range: 11% to 40%) of the maternal serum level. Starting at delivery, 30 mothers used zidovudine 300 mg, lamivudine 150 mg, lopinavir 400 mg, and ritonavir 100 mg orally twice a day; they were studied at 6, 12, or 24 weeks postpartum (10 at each time). On the study day, breast milk samples and maternal and infant plasma samples were collected before the maternal morning dose (about 14.9 hours after the prior evening dose) and 2, 4, and 6 hours after the maternal dose. Detectable quantities (at least 10 mcg/L) of ritonavir were found in 112 of 121 breast milk samples; over the 6 hours, average breast milk level was 79 mcg/L. Infants could breastfeed freely during the study period. This drug was not detectable (less than 10 mcg/L) in any of the 115 infant plasma samples. This drug was measured in 117 breastfed (90% exclusive) infants whose mothers were using lopinavir plus ritonavir for HIV infection during pregnancy and postpartum. At 8 and 12 weeks postpartum, none of the infants had detectable ritonavir plasma levels. At 12 weeks postpartum, 91% had ritonavir detectable in hair samples; average concentration was 0.15 ng/mg of hair (range: 0.03 to 0.42 ng/mg). According to author interpretation, infant exposure to this drug during breastfeeding is negligible.

Breastfeeding is not recommended during use of this drug; if replacement feeding is not an option, a different drug may be preferred. According to some experts, caution is recommended. Excreted into human milk: Yes Comments: -The effects in the nursing infant are unknown. -The US CDC, American Academy of Pediatrics, and manufacturer advise HIV-infected women not to breastfeed to avoid postnatal transmission of HIV to a child who may not yet be infected. -Local guidelines should be consulted if replacement feeding is not an option.

See references

References for pregnancy information

  1. "Product Information. Norvir (ritonavir)." Abbott Pharmaceutical, Abbott Park, IL.
  2. Panel on Treatment of HIV-Infected Pregnant Women and Prevention of Perinatal Transmission "Recommendations for Use of Antiretroviral Drugs in Pregnant HIV-1-Infected Women for Maternal Health and Interventions to Reduce Perinatal HIV Transmission in the United States. Available from: URL:" ([2016, Jun 7]):
  3. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  4. Melbourne: Therapeutic Guidelines Limited "eTG complete [Online] Available from: URL:" ([2014, Nov -]):
  5. Cerner Multum, Inc. "Australian Product Information." O 0

References for breastfeeding information

  1. Melbourne: Therapeutic Guidelines Limited "eTG complete [Online] Available from: URL:" ([2014, Nov -]):
  2. Fairbrothers D, Kirby E, Lester RM, Wegmann PC, Marshall F, Parkin WE "Recommendations for assisting in the prevention of perinatal transmission of human T-lymphotropic virus type III/lymphadenopathy-associated virus and AIDS." MMWR Morb Mortal Wkly Rep 34 (1985): 721-34
  3. Panel on Treatment of HIV-Infected Pregnant Women and Prevention of Perinatal Transmission "Recommendations for Use of Antiretroviral Drugs in Pregnant HIV-1-Infected Women for Maternal Health and Interventions to Reduce Perinatal HIV Transmission in the United States. Available from: URL:" ([2016, Jun 7]):
  4. United States National Library of Medicine "Toxnet. Toxicology Data Network. Available from: URL:" ([cited 2013 -]):
  5. "Product Information. Norvir (ritonavir)." Abbott Pharmaceutical, Abbott Park, IL.
  6. "Infant feeding and transmission of human immunodeficiency virus in the United States." Pediatrics 131 (2013): 391-6
  7. Cerner Multum, Inc. "Australian Product Information." O 0
  8. Newell ML, Dunn D, Peckham CS, Ades AE, Pardi G, Semprini AE "Risk factors for mother-to-child transmission of HIV-1." Lancet 339 (1992): 1007-12

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