### What you need to know A 48 year old woman presented to her general practitioner with a seven day history of colicky lower abdominal pain and vomiting. The intermittent colicky abdominal pain started first when it woke her from sleep. The next day she vomited twice. Her colicky abdominal pain continued, and she noted that it tended to occur about half an hour after eating. She continued vomiting once or twice a day. She reported no diarrhoea and had last opened her bowels six days earlier. On examination she was obese, had no abdominal scars, no abdominal hernias, had quiet bowel sounds, and non-specific generalised abdominal tenderness. There was no guarding or rebound tenderness. The rectum was empty. The general practitioner diagnosed constipation and prescribed a laxative. Three days later she was admitted to hospital with recurrent vomiting and dehydration. She was diagnosed with bowel obstruction due to a caecal carcinoma. Sub-acute small bowel obstruction implies an incomplete obstruction of the bowel lumen. Whereas patients with complete bowel obstruction rapidly become extremely unwell, patients with subacute small bowel obstruction or chronic large bowel obstruction may have colicky pain, abdominal distension and vomiting that are less pronounced …