Animal studies have revealed evidence of embryotoxicity and teratogenicity. Maternal toxicity (reduced food consumption and reduced body weight gain) and skeletal malformations (cranial malformations and missing ribs) were observed when this drug was given orally to pregnant rats during organogenesis at doses at least 27 mg/kg (at least 1.4 times the 400 mg twice daily oral suspension regimen based on steady-state plasma levels of drug in healthy subjects); the no-effect dose for malformations and maternal toxicity in rats was 9 mg/kg (0.7 times the exposure with the 400 mg twice daily oral suspension regimen). No malformations were observed when this drug was given to pregnant rabbits during organogenesis at doses up to 80 mg/kg (5 times the exposure with the 400 mg twice daily oral suspension regimen); the no-effect dose in rabbits was 20 mg/kg; at high doses of 40 and 80 mg/kg (3 or 5 times the clinical exposure), an increase in resorptions occurred and at 80 mg/kg a reduction in body weight gain of females and a reduction in litter size were observed. There are no controlled data in human pregnancy.

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 Not Assigned: The US FDA has amended the pregnancy labeling rule for prescription drug products to require labeling that includes a summary of risk, a discussion of the data supporting that summary, and relevant information to help health care providers make prescribing decisions and counsel women about the use of drugs during pregnancy. Pregnancy categories A, B, C, D, and X are being phased out.

This drug should not be used during pregnancy unless the benefit outweighs the risk to the fetus.

AU TGA pregnancy category: B3
US FDA pregnancy category: Not assigned.

Risk summary: Based on animal data, this drug may cause fetal harm when administered to pregnant patients; insufficient data available on use of this drug in pregnant women to inform a drug-related risk.

Comments:
-Effective contraception is recommended during therapy and for at least 2 weeks after the last dose; local protocol should be consulted regarding contraception timing.
-If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, the patient should be apprised of the potential harm to the fetus.

See references

Breastfeeding is not recommended during use of this drug; breastfeeding should be discontinued upon initiation of this drug.

Excreted into human milk: Unknown
Excreted into animal milk: Yes

Comments:
-Developmental and health benefits of breastfeeding should be considered as well as the mother's clinical need for this drug.
-The effects in the nursing infant are unknown; potential side effects in the breastfed child due to this drug or the mother's underlying condition should be considered.

See references