Multicenter Withdrawal Clinical Trials of N-acetyl Glucosamine Capsule for IBS-D Treatment

Inclusion Criteria:

• Man or woman, aged 18 to 65 years, inclusive.

• Based on the Roman III diagnostic criteria for diagnosis of IBS-D subjects, recurrentabdominal pain or discomfort (hard to describe the discomfort of pain), monthly attackwithin the past 3months at least 3 days. With two or more of the following three kindsof symptoms: At least a portion of the time abdominal pain or defecate increase when discomfort. At least a portion of the time abdominal pain or the row of loose stools when discomfort. At least a portion of the time abdominal pain or discomfort improved after defecation. Symptoms for at least 6 months before diagnosis

• Screening/import period pain intensity scores of the NRS week mean value are 3.0 plusand the days which at least more than one time a stool type are 6 or 7 type over 2days/week.

• Voluntarily signed the informed consent form

Exclusion Criteria:

• The absorption of any known adverse

• History of gastrointestinal surgery ( not including appendectomy)

• History of organic gastrointestinal diseases: IBS, cancer etc.

• History of chronic diseases: anemia (hemoglobin<90g/L), pulmonary tuberculosis,diabetes or cardiovascular, liver, kidney, brain, and hematopoietic system and otherserious diseases and psychiatric patients, AST(aspartate aminotransferase), ALT (alanine aminotransferase)> 1.5 times, BUN (blood urea nitrogen)> 1.2 times, Cr > 1.0times normal.

• The disease of lactose intolerance, gallstones, endometriosis, easily confused withIBS symptoms of ;

• Progressive weight loss;

• Concomitant medication is unable to stop but affect the gastrointestinal movement andfunction in the experiment, such as antibiotic drugs, the drugs of regulating theintestinal microecology;

• Concomitant medication use continuously for more than a week but affect thegastrointestinal movement and function in the experiment, such as parasympatheticinhibitors, nondepolarizing agent, antidiarrheal, opioid formulation, etc;

• Other researchers think not suitable for the list;