To Cher,
Your client's case sounds very interesting and she has done well to hang in
there.
Have you examined the baby's mouth?  If mom states that it feels like the
baby is biting maybe he is. What is his palate like, and tongue?  Maybe a
referral to a oral speech pathologist might be helpful.
In our practices we focus in on a problem but we know and sometimes forget
that many problems can be occuring or one is leading to others.  To treat
this mom for yeast sounded like the best start and there appears to be some
resolution but there may be other problems ( more related to baby ) and not
soley caused by yeast.
Hope she can experience some pain free nursings soon.

Ann Perry RN IBCLC