I went on Flagyly after a parasitic infection a few years back. I didn't have any bad reactions to it -- but, I was also already SO SICK from the parasite that I probably wouldn't! But, if you drink any amount of alcohol on Flagyl, you will vomit. Your doctor/pharmacist should have told you that.
Also, sometimes when I have the flu, I notice I actually feel better. I have hypothesized (no evidence for this fact), but because you are laid up in bed for a week - you are actually resting more than you normaly do on a "healthy" day. During the flu, I usually have one or two energy days -- and the crash -- because my body is technically happy for resting for a week. Maybe being so sick from medicine, was actually good for your CFS, because it forced you to rest?
Just a random thought...no scientific basis.
