So, when my son was diagnosed with Crohn’s and an abscess, he was immediately put on flagyl (metronidazole) and given a feeding tube, and by the next day there was already a huge improvement (abdominal pain nearly gone).
This led me to be very positively inclined toward antibiotics for treatment, and so we tried metronidazole a few more times later on as well as some other antibiotics.
Unfortunately, results were never quite like that first time. However, we did notice that amoxicillin definitely caused a significant reduction in pain multiple times, at least in the short term.
Will antibiotics fix the Crohn's and eliminate inflammation? Probably not. But in my experience they can be helpful in addition to other treatments, at least in the short-term. I doubt you'll continue to get much benefit from staying on them for more than a month.
However, I recommend *against* metronidazole (at least after the abscess is gone). Metronidazole has a lot of side effects--it causes nausea and bad taste in the mouth, it causes peripheral neuropathy, and there are some questions about it possibly being carcinogenic. I think you'll get most of the same benefits from amoxicillin or other much milder antibiotics.
