Flagyl did not agree with me at all, but it could have been that I had received Flagyl via IV in ER, then my doctor added Cipro. The combination did not work well for me and my dr. said Flagyl isn't really good (not strong enough) for DV and removed the Flagyl and kept me on Cipro only and it got much better.
Guess it depends on us as individuals -- tracking my meds and the results really helped my doctors know what works and what doesn't for me.