My spouse received a liver transplant in 12/2010 and I have been caregiving for him since. A fever exceeding 99 degrees should be addressed immediately by visiting ER. Throwing up. Each patient has transplant labs monthly or whatever the transplant team recommends. They should have provided you with info on what to look out for. Good luck. My spouse has had many ups & downs. Make sure you see a PC regularly, podiatrist, eye doctor, and dermatologist. They have skin issues.