Three patients with intestinal pseudo-obstruction secondary to multiple sclerosis are reported. This is a serious complication with significant morbidity and mortality, which is infrequently recognized in clinical practice and rarely reported in the medical literature.Keywords bowel obstruction; gastroparesis; intestinal pseudo-obstruction; multiple sclerosisIntestinal pseudo-obstruction is a rarely reported, but serious complication of multiple sclerosis that may lead to significant morbidity and mortality. It is likely to be due to interruption of neural pathways in the brainstem and spinal cord by primary demyelination and axonal loss.Case 1: A 49-year-old man had a history of multiple sclerosis of the primary progressive type for 18 years. His disease had caused severe disability with persistent diplopia, atonic bladder, requiring intermittent self-catheterization, and limitation of walking distance to 10 m with the aid of a walking frame. His comorbidities included obesity, hypercholesterolaemia, obstructive sleep apnoea (requiring continuous positive airways pressure support at night), and type 2 diabetes mellitus diagnosed 1 year previously. His current medications were: atorvastatin 20 mg daily, celecoxib 200 mg daily, amitriptyline 50 mg daily, baclofen 25 mg t.d.s and omeprazole 20 mg b.d. Three and a half years previously, he had developed severe abdominal pain and distension and was diagnosed with large bowel obstruction. At laparotomy, no mechanical obstruction was found and a defunctioning colostomy was made. Over the next 3 years, he had two further revisions to the stoma because of parastomal herniation. On the current admission, he underwent total colectomy. The histopathology showed greatly reduced colonic folds with colonic thickness of 2 mm and smooth muscle hypertrophy. There were three polyps ranging from 5 to 15 mm in diameter. There was no malignancy or diverticular disease. The findings were consistent with colonic pseudo-obstruction.Case 2: A 49-year-old woman had a history of multiple sclerosis for 12 years. This had caused severe disability. At the time of the current admission, she was unable to walk and, owing to gastroparesis and oesophageal dysmotility, was fed through a jejunostomy. She had significant cognitive impairment, had a longstanding indwelling catheter because of urinary incontinence and was incontinent of faeces. She also had depression and had recently ceased mianserin because of vomiting. Her current medications were: ranitidine 150 mg b.d., cisapride 10 mg t.d.s., salbutamol 5 mg nebule q.i.d. and sodium chromoglycate nebules 20 mg daily. She was admitted because of fever, tachycardia, tachypnoea and right basal crackles on chest auscultation. The chest X-ray was consistent with aspiration pneumonia. She was treated with oral antibiotics and improved over 5 days. On the sixth day of admission, she developed a new fever to 39°C and hypotension. She died the following day. Autopsy revealed colonic pseudo-obstruction and megacolon. There was also right lower lo...