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Tasimelteon Pregnancy and Breastfeeding Warnings

Brand names: Hetlioz, Hetlioz LQ

Medically reviewed by Last updated on May 29, 2023.

Tasimelteon Pregnancy Warnings

This drug should be used during pregnancy only if the potential benefit outweighs the potential risk.

US FDA pregnancy category: C

Animal studies have revealed evidence of embryolethality and embryofetal toxicity. Adverse effects included reduced fetal body weight, delayed ossification, delayed sexual maturation and physical development, and neurobehavioral impairment in offspring at doses greater than the recommended human dose (RHD). The highest dose not associated with adverse effects (30 mg/kg/day) is approximately 30 times the RHD. In animal fertility studies, estrus cycle disruption and decreased fertility were observed. The no-effect dose for female reproductive effects is approximately 2 times the RHD. There are no controlled data in human pregnancy.

US FDA pregnancy category C: Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

See references

Tasimelteon Breastfeeding Warnings

Caution is recommended.

Excreted into human milk: Unknown
Excreted into animal milk: Data not available

Comments: The effects in the nursing infant are unknown.

See references

References for pregnancy information

  1. Product Information. Hetlioz (tasimelteon). Vanda Pharmaceuticals Inc. 2014.

References for breastfeeding information

  1. Product Information. Hetlioz (tasimelteon). Vanda Pharmaceuticals Inc. 2014.

Further information

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