I have had very negative reactions to Flagyl. It makes me feel so nauseous and on the verge of vomiting the entire time I am on it. I haven't been on it in years, as my docs always prescribe something different due to my reactions. If it the side effects are worse than what it is meant to treat, I feel it's not worth it and would suggest you ask your physician for an alternative.
Best of luck!
Colleen