Use cups. My kiddos were already using them sometimes for water and juice by this age or earlier. They will need help at first, and will "wear" a lot of drinks for awhile, but that's the way it goes.....
As for formulas, I can't help much there because we were able to nurse. I would say keep trying different ones (buy the smallest boxes/cans until you find one baby likes). Maybe mix 2 together?? If none of them seem to work out, she could ask baby's dr. about going to whole milk a little earlier than the 12 months normally recommended.
Or maybe there's a homemade formula recipe out there that babies might like better?
Has your friend tried homeopathic remedies? It's my understanding that they are safe for nursing, but I don't know too much about them.
Also has she consulted La Leche League's research on which meds are safe for nursing? They are usually at the forefront of that sort of thing, sometimes ahead of some docs.
Good luck to your friend! I hope her health issues get resolved quickly and well!
K. Z.