Disposition of placentally transferred carbamazepine (Tegretol) in the newborn.

The plasma elimination of carbamazepine (Tegretol) was studied in five newborns who had got the drug transplacentally from their epileptic mothers. The half-lives ranged from 8.2-27.7 hours which is comparable or even shorter than those found in adults after a single oral dose, but in the same range as those found in adults after multiple oral doses. This suggests that the newborns' drug metabolizing capacity has been induced during fetal life.