While no diarrhea smells good, diarrhea that has an unusually foul smell can be an indicator of an underlying health problem. Antibiotic treatment for other problems is a common cause of foul-smelling diarrhea, but intestinal infections, impaired absorption and inflammatory bowel disease can also result in foul-smelling liquid stool. If your diarrhea doesn’t resolve within a few days, consult a physician for accurate diagnosis and appropriate treatment.
Antibiotic use can create an unhealthy shift in the balance of normally occurring intestinal flora. This can make the gastrointestinal system vulnerable to an overgrowth of Clostridium difficile, an anaerobic bacteria. Acute inflammation of the colon and diarrhea are caused by certain toxins produced by the bacteria. Treatment with cephalosporins, clindamycin or broad-spectrum penicillins is usually responsible, but any antibiotic can disrupt your natural gut flora. Taking probiotics during and after antibiotic treatment can help keep your intestinal flora healthy and able to resist Clostridium difficile and other opportunistic infections.
Commonly referred to as gastroenteritis, intestinal infections can cause foul-smelling diarrhea. Intestinal infections are caused by viruses, bacteria or parasites. Some of the most common organisms responsible for foul-smelling diarrhea include Escherichia coli, Salmonella, Shigella, rotavirus, Norwalk virus and Giardia. You can become infected by ingesting contaminated food or water or by being in contact with another infected person.
Impaired absorption of nutrients from the small intestine is also called malabsorption. Several conditions are known to cause malabsorption, including celiac disease, short bowel syndrome, tropical sprue, whipple's disease, carbohydrate intolerance and gastrointestinal infection. One of the symptoms of malabsorption is foul-smelling diarrhea. A doctor can examine you and run specific tests to identify the cause of the malabsorption and diarrhea.
Inflammatory Bowel Disease
Inflammatory bowel disease, IBD, is characterized by chronic inflammation of the gastrointestinal tract. Two different conditions, Crohn's disease and ulcerative colitis, comprise the spectrum of IBD. While they are distinct conditions with different symptoms, either one may cause foul-smelling diarrhea. Rectal bleeding is also common, especially in ulcerative colitis. Imaging and sigmoidoscopy are usually required for accurate diagnosis and treatment.
- GP Notebook: Antibiotic Associated Diarrhoea (AAD)
- "The Merck Manual of Diagnosis and Therapy"; Mark H. Beers, M.D., Robert Berkow, M.D.; 1999
- "Rosen's Emergency Medicine: Concepts and Clinical Practice 7th edition"; John A. Marx, M.D.; 2010