I don't know anything about skullcap, except from my days (very few) of
religion.  But St. John's Wort should be avoided.  It is not
incompatible with breastfeeding, but why use a drug just because it's an
herb?  An MAO inhibitor is a dangerous drug for the mother, and severe
side effects may occur if she eats certain types of cheese or drinks red
wine while taking an MAO inhibitor.  A drug is a drug.  If this mother
needs a drug for depression, in this case the herb may not be better.
There are drugs for depression which are safer for her and are fine for
breastfeeding.  I have nothing against herbs.  Indeed, I suggest them
for certain things, but if an herb works, it's because there is
something in it which is a drug.  Natural source does not make it safer.

Jack Newman, MD, FRCPC