Excluded loop syndrome: a complication of jejuno-ileal bypass for obesity.

Excluded loop syndrome may develop in patients who undergo jejuno-ileal bypass surgery with the excluded small intestine drained via an ileosigmoidostomy. A unique case of a morbidly obese male who underwent the procedure while on methadone maintenance therapy is presented. The major factor in the development of this disorder appears to be the high intraluminal pressures within the sigmoid colon which prevent adequate egress from the excluded loop. Narcotic medications tend to induce or intensify the syndrome.