I don't know about those two specific side effects, but Byetta is not a wonderful drug.  I had many side effects that included nausea and vomiting, abd. pain, diarrhea, and hair loss.  I did work, but who wants all of these side effects.  The worst is the fact that the abd. pain was so bad, I had to go to the ER, and they did a CT scan that showed an inflammation of the head  of the pancreas.  Byetta does cause pancreatitis, so this the last straw.  I've been off of it now for a few weeks, on Amaryl, and my glucose levels are great, no more abd. pain or nausea/vomiting, but my hair is still falling out.  I caution anyone who is on/thinking about going on byetta....