Neuromuscular disease of the gastrointestinal tract. Gastrointestinal motility is the function of gastrointestinal smooth muscle. It is controlled by both the intrinsic and extrinsic nerves of the gastrointestinal tract and, to a lesser degree, the gastrointestinal hormones. Therefore, any abnormality of the above factors, theoretically, can cause gastrointestinal dysmotility. In a clinical situation, commonly seen is gastrointestinal dysmotility caused by either smooth muscle or intrinsic and extrinsic nerves dysfunction. Diseases that cause smooth muscle dysfunction include familial visceral myopathies, nonfamilial visceral myopathies, collagen disease, muscular dystrophies, amyloidosis, thyroid disease, and so on. Diseases that cause enteric nerve dysfunction include familial visceral neuropathies, nonfamilial visceral neuropathies, diabetes mellitus, Chagas' disease, ganglioneuromatosis of the intestine, visceral neuropathy of carcinomatosis, Parkinson's disease, and so on. The patients with neuromuscular disease of the gastrointestinal tract have a wide range of clinical manifestations regardless of the underlying cause. At one end of the spectrum, the patients may be asymptomatic, and at the other end of the spectrum, the patients may have functional obstruction of the gastrointestinal tract. Plain abdominal x-rays, upper gastrointestinal (UGI) and small bowel x-rays, enteroclysis, barium enema, and manometric studies are useful for the work-up of these patients. Enteroclysis is especially helpful in ruling out mechanical obstruction of the small intestine in patients with chronic intestinal pseudo-obstruction. Treatment is mainly symptomatic and supportive. There is no effective drug to improve gastrointestinal motility. Surgery may be helpful in selected cases of severe gastrointestinal dysmotility. 