Phenytoin and carbamazepine in production of cleft palates in mice. Comparison of teratogenic effects.

The teratogenic activity of two anticonvulsant drugs, phenytoin sodium and carbamazepine, was studied in pregnant mice fed phenytoin and carbamazepine during days 8 to 13. Incidence of palatal defects and other abnormalities correlated with increasing dosages and blood levels of the drugs. Phenytoin produced a much higher incidence of teratogenic effects than carbamazepine.