I'm coming into this post late, but I definitely related to your reaction to the Avonex. I have only been on it for a few weeks, so I am kinda new to it, but that first shot was horrible. It was worse than any flu I have ever had. At least the symptoms are getting better now. I have the prefilled syringes, but I do remember the nurse saying the symptoms weren't as bad with the powder form. I hope this works out better for you.
Diagnosed with MS March 2008