Carbamazepine (Tegretol) and valproic acid (Depekane) will get into
the milk in small amounts.  When you weigh the risks of not
breastfeeding against the risks of this small amount of medication
which we use for infants, I would say it is better to breastfeed.
Usually, the baby has been getting this drug from conception to birth
already.  We use both these medications in children, often quite
small.

Jack Newman, MD, FRCPC