I got a call from a pharmacist at our local hospital who was questioning me
to see I told a mom (the one I recently wrote about) that she MIGHT be able
to breastfeed if she timed her nursings for a certain length of time after
taking the medications.  He could not understand this at all saying that if
milk is always being produced than it would meal that medication is entering
the milk even at times when serum levels are peaking and therefore the
medication would be in the  milk as it is stored and would go to the baby at
the same levels regardless of when the baby was fed.  (that's essentially
what he was saying or asking).  I always remember speaking about timing feeds
for example before smoking, or now we say 6 hours after consuming alcohol,
and recently I've seen posts that mention timing feeds specific lengths of
time after taking specific medications.  The pharmacist want to know where we
get this concept from and could not respond to him.
I would love to be able to send him something concrete as well as get a
clearer understanding for myself.  I think his point did make sense.  He said
just because the xanax has a short half life (or any other medication for
that matter), it didn't make that much of a difference to what would be in
the milk at the time of the feed.  By the way, the main reason he called was
that this mom, who I hadn't counseled since early in her pregnancy and at
that time told her she might be able to breastfeed on xanax because it was
not one of the absolutely contraindicated meds (but that I would have to look
into it) and then she never contacted me again - went and delivered her baby
and when the staff said absolutely no breastfeeding she boldly announced that
Jill Meltzer, the breastfeeding coordinator said it was okay.  COULD YOU
PLOTZ?  (that's all I need is to be considered the adversary).  Anyway could
anybody supply me with information where LLL or other's in field of
breastfeeding got the notion of timing feeds after or before certain
medications affected the amount of the dose that the baby gets.  I don't
think the medication gets reabsorbed from the milk back into the bloodstream
so what happens to it and by what mechanism?  I hope we have some
pharmacology specialists lurking out there over this holiday weekend.
Enjoy your weekend everybody,
Jill Meltzer, R.N.
Breastfeeding Coordinator
WIC Program