Abdominal aortic aneurysm
Aortocaval fistula
Acute gastroenteritis
Aortoenteric fisulta
Appendicitis (early)
Bowel obstruction
Large bowel obstruction
Ogilvie's syndrome
Small bowel obstruction
Malignant bowel obstruction
Bowel perforation
Gastroparesis
Diabetic ketoacidosis
Hernia
Inflammatory bowel disease
Mesenteric ischemia
Mesenteric vein thrombosis
Pancreatitis
Peritonitis
Sickle cell crisis
Spontaneous bacterial peritonitis<unk> 
Aortocaval fistula
Large bowel obstruction
Ogilvie's syndrome
Small bowel obstruction
Malignant bowel obstruction
Ogilvie's syndrome
Mesenteric vein thrombosis
Behavioral-related
Lack of exercise
Diet-related
Fecal impaction
Stercoral colitis
Diverticulitis
Bowel obstruction
Small bowel obstruction
Large bowel obstruction
Ogilvie's syndrome
Malignant bowel obstruction
Specific causes: tumor, stricture, hernia, adhesion,<unk> 
Painful anorectal disorders (e.g. anal fissure, hemorrhoids)
Medical causes
Hypothyroidism 
Electrolytes
Hypomagnesia
Hypercalcemia
Hypokalemia
Medication-related
Opiods, antipsychotics, anticholinergics, antacid, antihistamines
Constipation (peds)
Lack of exercise
Diet-related
Small bowel obstruction
Large bowel obstruction
Ogilvie's syndrome
Malignant bowel obstruction
Specific causes: tumor, stricture, hernia, adhesion,<unk> 
Ogilvie's syndrome
Hypothyroidism 
Electrolytes
Hypomagnesia
Hypercalcemia
Hypokalemia
Hypomagnesia
Hypercalcemia
Opiods, antipsychotics, anticholinergics, antacid, antihistamines
Volvulus
Abdominal aortic aneurysm
Rectal foreign body
Aortocaval fistula
Anal fissure
Acute gastroenteritis
Fecal impaction
Aortoenteric fisulta