I would guess that the drug is isoniazid.  If that is all the mother is
taking does she actually have active TB, or did she merely convert on
her skin test?  We surely do not treat active TB in this day and age
with only one drug, do we?  Thus the question of whether the mother is
sputum positive does not come up here, as she is not, at least from the
info given.

There is no reason for the mother not to breastfeed on isoniazid.  If
the baby became positive, we would treat him with isoniazid.

Breastfeeding should continue even if the baby did take a bottle, for
goodness sakes.  That should not even be in the equation.

Jack Newman, MD, FRCPC