What Is Causing Vomiting Reaction To NSAIDS?

I have problems with diarrhea, food intolerances, weight loss, and other symptoms for about 15 years. in particular, I cannot eat beef or dairy, and lately anything with significant protein (like peas, beans, etc). However, when I have taken the following medications (for long periods), the symptoms have stopped completely: Ibuprofen, celebrex, lamisil (oral tablets), diflucan (although cause a rash in my mouth). I can t take most of these now, I have a vomiting reaction to NSAIDS, and diflucan cause a mouth rash, lamisil is for short term use. Any ideas what could be causing this? if so, suggested Tx s to talk to my doctor about? Also, I have been tested for celiac disease, and the results are ambiguous, though an intestinal biopsy was negative. Gluten free diet for 1 year was no help. I have had 3 colonoscopies, all normal. Also, I have pernicious anemia, which docs have suggested is autoimmune ( I take sublingual tabs to control). Looking forward to your thoughts.