persistant rash on the nipple?

I'm wondering if anyone here has had this particular problem. A friend of
mine has a 4 month old baby who EBF's. Every two weeks or so my friend gets
an uncomfortable rash on her nipple/areola. It lasts for a few days, isn't
quite painful but uncomfortable and then the skin peels off and the rash
goes away. No one at LLL or at her peds office has any ideas and she is
between insurances so she can't go to her OB right now. Ped says that baby
doesn't have thrush.

It sometimes happens on one, sometimes both breasts.

Anyone? Any ideas?

TIA!
Molly