Clinically diarrhea is called diarrhea, diarrhea more than 1 year belongs to the category of chronic diarrhea, its causes are more complex, may be due to unclean diet, emotional depression, inadequate conditioning after illness, and then the gastrointestinal tract can not digest and absorb food normally, long-term past chronic diarrhea, generally need to improve for the cause. In addition, chronic diarrhea is also associated with functional and organ lesions of the intestinal tract or systemic diseases: 1, ulcerative colitis: is a chronic non-specific inflammatory disease of the intestinal tract involving the rectum and colon, often caused by a variety of factors such as environmental, genetic, intestinal microorganisms, immune, etc. imbalance in the immune system of the intestinal mucosa, and then sustained inflammatory damage, there are persistent or recurrent episodes of diarrhea, up to 1 year, or even decades; 2 , Crohn’s disease: is a chronic inflammatory granulomatous disease of the gastrointestinal tract of unknown etiology, with genetic susceptibility, caused by a variety of factors. Such as chemical environment plus genetic susceptibility to infection, the role of intestinal flora to their own intestinal mucosa abnormal immune response, which in turn causes long-term diarrhea, as well as abdominal pain, weight loss, etc.; 3, irritable bowel syndrome: often caused by visceral hypersensitivity, abnormal gastrointestinal dynamics, can cause increased gastrointestinal motility, resulting in persistent diarrhea; 4, chronic pancreatitis: can cause organic indigestion, affecting Gastrointestinal digestive capacity, and chronic diarrhea can occur in the long term; 5, intestinal tuberculosis: is a chronic specific infection of the intestine caused mainly by Mycobacterium tuberculosis of human type, which can cause long-term stimulation of the intestine and affect the function, and thus chronic diarrhea.