Arizona,
Flagyl is also known as Metronidazol and is often prescribed for people with IBD - either Crohn's or Colitis. I can't say that even doctors fully understand why it helps with a flare, but it does for many, even though side effects can be unpleasant.
Flagyl is an antibiotic and tends to kill off bad bacteria in the gut that can cause inflammation which can lead to a flare.
Many IBDers report feeling better while on Flagyl and worse again once off of it for a week or so.
I have Colitis and take Asacol and very good probiotics, which are the good gut bacteria, daily. When I have a flare I sometimes double or triple my dose of probiotics and it does seem to help.
Since your son is 7 years old, though, you should be sure to discuss any treatments with his doctor, even probiotics to make sure they won't adversely react with any of his other treatments.
Best,
Elizabeth
Important:
We hope you find this general health information helpful. Please note however, that this Q&A is meant to support not replace the professional medical advice you receive from your doctor. No information in the Answers above is intended to diagnose or treat any condition. The views expressed in the Answers above belong to the individuals who posted them and do not necessarily reflect the views of Remedy Health Media. Remedy Health Media does not review or edit content posted by our community members, but reserves the right to remove any material it deems inappropriate.