Everytime I come off the Flagyl four days later I have a fever and the pain around my fistula ramps up.
Hi Sailorluna, I 've been experimenting something similar until my last resection surgery, which gave me some relief.
I don't know if exactly what you feel is, but in my case I used the Antibiotics for killing the excess of bacteria, which causes badabsorption, gases and discomfort.
http://en.wikipedia.org/wiki/Small_bowel_bacterial_overgrowth_syndrome
So, after getting worse every time I come off the Flagyl many times, I ended up having 250 mg of antibiotics every other day.
The bad side of having antibiotics for log time is that your body may get used to it, so in case of needing it for another issue, it would cause no effect.
I tried many antibiotics by medical advice, and the ones that worked better for me were Metronidazole (Flagyl) and Rifaximin. Rifaximin is almost as good as Flagyl (in my own experience) and it is said to have less side effects because it goes straight to the colon, so the rest of your body is not being affected to it.
http://en.wikipedia.org/wiki/Rifaximin
I hope this helps. You can investigate this and ask your doc about it.