Examples

How It Works

Metronidazole, an antibiotic, destroys certain bacteria, which may help control infection and inflammation in the intestines.

Why It Is Used

Metronidazole may be used to:

• Treat infections that develop because of Crohn's disease, especially when abscesses, abnormal connections (fistulas) between two parts of the intestines, or holes in the intestines or anal area occur.
• Treat active disease. Metronidazole may help with symptoms when aminosalicylates do not.
• Keep symptoms of Crohn's disease from coming back after surgery.

How Well It Works

Studies have shown that metronidazole can be effective in keeping symptoms of Crohn's disease from coming back after surgery.¹

Other studies have shown that metronidazole relieved symptoms of Crohn's disease, especially in the colon. For some people, it worked better than sulfasalazine.² But antibiotics don't work as well after you take them for a long time, and some people have severe side effects. Metronidazole is not used very often to treat Crohn's disease for the long term or to keep the disease in remission (a period without symptoms).

Metronidazole may be used in combination with other antibiotics or other medicines.

Side Effects

The most common side effects include:

• An unpleasant metallic taste in the mouth.
• Vaginal yeast infections in women.
• Nausea.

Drinking alcohol while taking metronidazole can cause severe nausea, vomiting, and flushing.

Tingling or numbness in the fingers and toes (peripheral neuropathy) can happen with long-term use.

See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

What To Think About

Some experts think that infectious organisms such as bacteria may play a role in the development of inflammatory bowel diseases. But this has not yet been proved. Intestinal infections can cause flare-ups of Crohn's disease or ulcerative colitis.

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