I have been allergic to Aspirin and Ibuprofen for about the last 20 years. I am a 50 year old man and have a laundry list of physical issues that could be helped by an anti inflammatory such as Advil or Aleve. I have not taken either medicine in over 12 years as the last time my whole face swelled up and I had to go to urgent care to get a steroid injection. My symptoms before that were breaking out in hives and getting red and blotchy. My question is I am curious if there is a way to slowly introduce an ibuprofen product to 1) see if I still have the allergy and 2) if I can very slowly develop my tolerance to a level where I can again occasionally use this.