Avonex was introduced in 1996 to reduce the severity and frequency of MS
attacks.  If I remember my reading right (unfortunately I didn't save the
detailed information I had about it), it works on the immune system, because
MS is an autoimmune disease.  My speculation is that it would be inadvisable
to get pregnant because pregnancy alters the normal immune system state, NOT
because Avonex is a teratogen - however, you obviously can't be too
cautious.  I don't recall reading anything about its effect on
breastfeeding.  I believe it's only available via injection?  (wish I'd
saved that newsletter!)

The National Multiple Sclerosis Society in the US is a wonderful source of
information about all aspects of MS.  Their website is <http://www.nmss.org>
and they can be reached by phone at 1-800-FIGHT MS (344-4867).  I am quite
sure that you can get all sorts of good information about Avonex.  They may
not be able to say "yes, breastfeed," or "No, don't breastfeed," but the
information about the makeup of the drug, its route of administration, its
dosing schedule, and how it works to fight MS exacerbations may provide the
information needed to make a deduction about whether breastfeeding can
continue.  I'm betting that it can!

Best wishes to this mother.  The diagnosis of MS is a scary time.  She needs
to know that 75% of people with MS do NOT end up in wheelchairs;  many/most
people with MS are indistinguishable from the general population most of the
time.  There's a book called "Multiple Sclerosis," author Rosner (?I think -
pretty sure) - originally published in the late 80s and revised a few years
ago - it's excellent, informative and very reassuring.  I highly recommend it.

Mary Renard, RN, BSN, IBCLC