I have been on tysabri for close to 4years and I did notice the difference when I went without it for almost two months. Lately I have been breaking out in hives, rashes and bumps. It could be the Provigil and tysabri but it could be poison ivy from working out in the yard. I noticed the rash I had all the sudden got worse and spread, is it a coincidence that I had a tysabri treatment today? I am so sick of all of this, never a straight answer for any symptoms, just want to feel normal again.