The use of metronidazole (Flagyl) in Crohn's disease.

The efficacy of metronidazole in the treatment of Crohn's disease remains unproven. It has not been superior to a placebo in three small studies. Uncontrolled reports suggest it may be of benefit in selected patients who have not responded to previous medical or surgical therapy. Metronidazole therapy can lead to complete healing of perineal fistulas. Persistent concerns over side-effects, carcinogenicity, and bacterial resistance suggest that drug should be prescribed with caution for long-term use.