Intestinal pseudo-obstruction (IP) is an uncommon disorder of gut motility which must be differentiated from mechanical intestinal obstruction. We have seen 11 such patients over the last 5 years. Characteristic symptoms, shared by mechanical obstruction, include abdominal distention and pain, nausea, and vomiting. Radiologic studies reveal dilated loops of bowel with air fluid levels. In most patients a major differentiating feature from obstruction may be the presence of diarrhea rather than obstipation. Steatorrhea is secondary to an overgrowth of anaerobic bacteria in the motionless dilated loops of bowel. IP has been associated with various disorders: in our series two patients had scleroderma, one multiple small bowel diverticula, one systemic amyloidosis, one celiac disease, and one spinal cord injury; in only two patients was the disorder considered "idiopathic." Three patients had previously undergone a jejuno--ileal bypass for morbid obesity. During the acute episode, the patients were treated symptomatically with decompression by nasogastric or rectal tube with fluid and electrolyte replacement. Malabsorption treated with broad spectrum antibiotics reversing the steatorrhea but not episodes of pseudo-obstruction. Magnesium deficiency was present in seven patients and its correction resulted in amelioration of the symptom complex. In two patients episodes of pseudo-obstruction were markedly reduced by metoclopramide which was not effective in two others.