This drug should be used during pregnancy only if clearly needed

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

Risk Summary: There are no adequate data on the developmental risks associated with use in pregnant women; studies in pregnant animals have shown developmental toxicity at clinically relevant doses.

Comments:
-There are pregnancy risks related to epilepsy and antiepileptic medications; healthcare providers should advise women who are pregnant or plan to become pregnant of these risks.
-Women of childbearing potential should use contraceptive measures during treatment; concomitant use of this drug with hormonal contraceptives containing ethinyl estradiol or norethindrone may be less effective and alternative or an additional non-hormonal forms of contraception may be needed (see drug interactions).
-There are pregnancy registries that monitor pregnancy outcomes in women exposed to antiepileptic drugs during pregnancy: North American Antiepileptic Drug (NAAED) Pregnancy Registry (1-888-233-2334 or http://www.aedpregnancyregistry.org); Australian Pregnancy Register for Women on Antiepileptic Medication (1 800 069 722).

Animal studies have not shown teratogenicity, but fetotoxicity in the presence of maternal toxicity has been observed. Decreased fetal weights and increased incidences of fetal skeletal abnormalities were observed in rats and rabbits at doses associated with maternal toxicity. Human risks related to epilepsy and antiepileptic drugs during pregnancy include an increase in malformations with polytherapy and the potential for increased seizures with abrupt discontinuation which may be detrimental to both mom and fetus. There are no adequate and well-controlled studies in pregnant women.

No data are available on the fertility effects on human; however, rats exposed to clinical concentrations and higher have shown decreased fertility (a reduced fertility index in females and decreased spermatozoa counts in males at 3 times clinical exposure and decreases in implants and live embryos at approximately 2 times clinical exposure).

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.

See references

Animal studies suggest that this drug is likely to be excreted in human milk.

A decision should be made to discontinue breastfeeding or discontinue the drug, considering the importance of the drug to the mother

Excreted into human milk: Unknown (likely)
Excreted into animal milk: Data not available

Comments: Breastfeeding should be avoided during maternal therapy due to the potential for serious adverse reactions in breastfed infant from this drug.

See references