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Ambrisentan Pregnancy and Breastfeeding Warnings

Ambrisentan is also known as: Letairis

Ambrisentan Pregnancy Warnings

Use is contraindicated.

AU TGA pregnancy category: X
US FDA pregnancy category: X

Comments:
-Pregnancy testing should be performed before the initiation of treatment, monthly while on treatment, and for 1 month after stopping treatment.
-Acceptable methods of contraception should be used during treatment and for 1 month after stopping treatment.
-Acceptable methods of contraception include 1 highly effective form (intrauterine device (IUD), contraceptive implant, or tubal sterilization) or a combination of methods (hormone method with a barrier method or 2 barrier methods); if a partner's vasectomy is decided as 1 method of contraception, a hormone or barrier method should also be used.
-Counsel patients on pregnancy planning and prevention, including emergency contraception.
-Women should not become pregnant for at least 3 months after stopping treatment (AU).

Drug is expected to cause fetal harm if administered to pregnant women. Animal data have revealed teratogenicity in rats and rabbits. In both species, there were abnormalities of the lower jaw and hard and soft palate, malformation of the heart and great vessels, and failure of formation of the thymus and thyroid. Teratogenicity is a class effect of endothelin receptor antagonists. There are no data on the use of ambrisentan in human pregnancy. Use is considered contraindicated in pregnancy.

The effect of ambrisentan on male human fertility is unknown, but it appears endothelin receptor antagonists may have an adverse effect on spermatogenesis. In a 6-month clinical trial with bosentan, another endothelin receptor antagonist, a decline in sperm count of at least 50% was observed in at least 25% of patients after 3 to 6 months; however in 22 of 25 patients who completed 6 months of treatment, sperm count remained within normal limits with no changes in sperm morphology, sperm motility, or hormone levels.

AU TGA pregnancy category X: Drugs which have such a high risk of causing permanent damage to the fetus that they should not be used in pregnancy or when there is a possibility of pregnancy.

US FDA pregnancy category X: Studies in animals or humans have demonstrated fetal abnormalities and/or there is positive evidence of human fetal risk based on adverse reaction data from investigational or marketing experience, and the risks involved in use of the drug in pregnant women clearly outweigh potential benefits.

See references

Ambrisentan Breastfeeding Warnings

(UK) Use is contraindicated.
(AU, US) 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: Unknown
Excreted into animal milk: Yes

Comments: The effects in the nursing infant are unknown.

See references

References for pregnancy information

  1. "Product Information. Letairis (ambrisentan)." Gilead Sciences, Foster City, CA.
  2. Cerner Multum, Inc. "Australian Product Information." O 0
  3. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

References for breastfeeding information

  1. "Product Information. Letairis (ambrisentan)." Gilead Sciences, Foster City, CA.
  2. Cerner Multum, Inc. "Australian Product Information." O 0
  3. 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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