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Hydrochlorothiazide / losartan Pregnancy and Breastfeeding Warnings

Hydrochlorothiazide / losartan is also known as: Hyzaar

Medically reviewed on Jul 18, 2017

Hydrochlorothiazide / losartan Pregnancy Warnings

Animal studies have revealed evidence of fetal and neonatal toxicity and mortality. In humans, use of drugs that act on the renin angiotensin system (RAS) during the second and third trimesters increases fetal and neonatal morbidity and death. There are no controlled data in human pregnancy.

US FDA pregnancy category D: There is positive evidence of human fetal risk based on adverse reaction data from investigational or marketing experience or studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

UK: Use is not recommended during the first trimester of pregnancy and is contraindicated during the second and third trimesters.
US: This drug should not be used during pregnancy unless there are no alternatives and the benefit outweighs the risk to the fetus.

US FDA pregnancy category: D

Comments: Adequate methods of contraception should be encouraged.

See references

Hydrochlorothiazide / losartan Breastfeeding Warnings

Use is not recommended and a decision should be made to discontinue breastfeeding or discontinue the drug, taking into account the importance of the drug to the mother.

Excreted into human milk: Yes (hydrochlorothiazide); Unknown (losartan)
Excreted into animal milk: Yes (losartan)

See references

References for pregnancy information

  1. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0
  2. "Product Information. Hyzaar (losartan-hydrochlorothiazide)." Merck & Co, Inc, West Point, PA.

References for breastfeeding information

  1. "Product Information. Hyzaar (losartan-hydrochlorothiazide)." Merck & Co, Inc, West Point, PA.
  2. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

Further information

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

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