I don't know for sure if I had a stevens-johnson reaction or not to sulfasalazine, but I think my reaction bordered on this. My rheumy put me on sulfasalazine for rheumatoid arthritis. Keep in mind, I had never had an allergy to sulfa drugs before. After about 5 weeks on the drug, I developed a high fever with severe joint pains. I called my rheumy and he told me to see my primary; it sounded like I had a virus. Went to primary and he gave me a toradol injection for the joint pain and sent me home. Ended up in ER in the middle of the night for the severe joint pain, and received a prescription for prednisone. The very next day, I broke out in a rash from head to toe, in my mouth, ears, nose, etc... It was awful. My platelets also dropped dangerously low (that's why I know it was attributed to the sulfasalazine). I started taking high dose prednisone on a Friday; by Monday, my platelets had returned to normal (rheumy ordered blood work that Monday) and my rash had almost cleared up. I probably should have gone back to the ER when I noticed the rash, but I just couldn't face it again, and the prednisone had helped my joint pains greatly. Had I gone, I fear I would have been admitted. Was it a full-blown stevens-johnson reaction--probably not. I think I would have been much sicker if that were the case, but I feel it came pretty close. My rheumy said had I not started taking the prednisone on my own, between my platelets and this rash, things could have been much much worse. I will never touch another sulfa drug again. Unfortunately, drug reactions are often quite severe and can be fatal. Fortunately, they are also rare. Glad you found out about your sulfa allergy so you can avoid it in the future.