What does it take for the pediatricians to understand?  If the mother
is getting the maximum dose, it does not mean that there is some
overflow phenomenon as there is, say with glucose in the urine.  If
the baby gets approximately 1% of the total maternal dose, he usually,
gets about the same, regardless of the total dose, though there may be
some variability, since protein binding, for example, may change with
total dose.  So, if the mother gets 1200 mg of carbamazepine daily
(about the maximum dose), the baby will get, if he gets 1%, 12 mg/day.
If she is on a small dose, say 200 mg/day, he will get 2 mg.  The
difference between the two is pretty minimal.

The pediatrician seems to want the mother not to succeed at
breastfeeding, since the information he has given her is likely to
achieve that end.

Jack Newman, MD, FRcPC