I also have unpredictable reactions to medication. Anyphlaxis to morphine and demerol...rashes from antibiotics. I took a quarter of a Dramamine pill when flying and had to be taken off the plane in a wheel chair...so doped I couldn't feel my legs. When I got shingles last year, I took the first anti-viral dose in the doctors office to make sure I didn't have a reaction. It's really frustrating and frightening. Don't know if this is a fibro-thing...some of these reactions came long before I was diagnosed.
Donna