Skip to Content
Here’s what to ask a doctor about hereditary angioedema

Omeprazole Pregnancy and Breastfeeding Warnings

Omeprazole is also known as: Omesec, Prilosec, Prilosec OTC, Zegerid (Original Formulation)

Omeprazole Pregnancy Warnings

Omeprazole has been assigned to pregnancy category C by the FDA. Omeprazole has been used during labor and delivery to prevent Mendelson's syndrome. Omeprazole should only be given during pregnancy when benefit outweighs risk.

Some animal studies have revealed evidence of embryolethality, embryo/fetal toxicity, and postnatal developmental toxicity. Animal studies with esomeprazole (an S-isomer of omeprazole) revealed changes in bone morphology in offspring of rats dosed through most of the pregnancy and lactation with doses equal to or greater than approximately 33.6 times an oral human dose of 40 mg. There are no adequate and well-controlled studies in human pregnancy. Available epidemiologic data failed to demonstrate an increased risk of major congenital malformations or other adverse pregnancy outcomes with use of omeprazole in the first trimester. Several studies have reported no short-term adverse effects in infants whose mothers where treated with a single dose of oral or intravenous omeprazole as premedication for cesarean section under general anesthesia. An expert review of published data of omeprazole use during pregnancy by the Teratogen Information System concluded that therapeutic doses during pregnancy will not likely pose a substantial teratogenic risk. Data pertaining to the use of omeprazole during pregnancy are limited. In one study, omeprazole 80 mg was administered orally one time to prevent Mendelson's syndrome in 20 women with uncomplicated pregnancies of at least 36 weeks duration (mean, 38.3 weeks) requiring scheduled Cesarean section. Cesarean section was done approximately 13 to 16 hours after the dose. Omeprazole was undetectable (<20 nmol/L) in umbilical vein samples from 16/20 infants. Omeprazole was undetectable in umbilical artery samples from 10/17 infants. There were no apparent adverse effects in the neonates.

See references

Omeprazole Breastfeeding Warnings

Omeprazole concentrations have been measured in human milk. The peak concentration in breast milk was less than 7% of the peak serum concentration or 0.004 mg of omeprazole in 200 mL of milk. Since omeprazole is excreted in the breast milk, and because of a potential for serious adverse reactions in nursing infants and the possibility for tumorigenicity in animals, the manufacturer recommends that a decision should be made to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother. Other manufacturers recommend exercising caution when used in nursing women.

See references

References for pregnancy information

  1. Lalkin A, Loebstein R, Addis A, RamezaniNamin F, Mastroiacovo P, Mazzone T, Vial T, Bonati M, Koren G "The safety of omeprazole during pregnancy: A multicenter prospective controlled study." Am J Obstet Gynecol 179 (1998): 727-30
  2. Brunner G, Meyer H, Athmann C "Omeprazole for peptic ulcer disease in pregnancy." Digestion 59 (1998): 651-4
  3. Moore J, Flynn RJ, Sampaio M, Wilson CM, Gillon KR "Effect of single-dose omeprazole on intragastric acidity and volume during obstetric anaesthesia." Anaesthesia 44 (1989): 599-62
  4. Stewart CA, Termanini B, Sutliff VE, Corleto VD, Weber HC, Gibril F, Jensen RT "Management of the zollinger-ellison syndrome in pregnancy." Am J Obstet Gynecol 176 (1997): 224-33
  5. Kallen B "Delivery outcome after the use of acid-suppressing drugs in early pregnancy with special reference to omeprazole." Br J Obstet Gynaecol 105 (1998): 877-81
  6. "Product Information. Prilosec (omeprazole)." Merck & Co, Inc, West Point, PA.

References for breastfeeding information

  1. "Product Information. Prilosec (omeprazole)." Merck & Co, Inc, West Point, PA.

See Also...

Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Wolters Kluwer Health and is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This drug information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate that the drug or combination is safe, effective, or appropriate for any given patient. Multum Information Services, Inc. does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. Copyright 2000-2008 Multum Information Services, Inc. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse, or pharmacist.