Diarrhea-predominant irritable boewl syndrome(IBS-D) seriously affect the quality of life in patients. Clinically, it is effective to apply therapeutic method of clearing heat and promoting diuresis to the common syndrome of dampness-heat. Dysbiosis of intestinal microbiota is closely related to the immune imbalance and intestinal mucosal barrier injury. C1orf106/CYTH-1/ARF6 signal pathway, which derive from intestinal micro environment changes,is the mainly cause of intestinal mucosal barrier injury, and this is may be the common pathogenesis of dampness-heat syndrome in IBS-D . Based on the clinic, the project is to study the effect and mechanism of Chinese compound formula of clearing heat and promoting dieresis in modulating intestinal microbiota dysbiosis, repairing intestinal mucosal barrier and reconstructing intestinal microenvironment. With the combination of metagenomics and metabonomics, the study compare the differences of co-metabolites of intestinal microbiota and host within the healthy people, IBS-D patients with dampness-heat syndrome, to explore the relevance between intestinal flora and host co-metabolites. Furthermore, the experimental study is to clarify the drug targets via C1orf106/ CYTH-1/ARF6 signal pathway.Through the study of association between dampness-heat syndrome in IBS-D and intestinal microbiota, it is of important academic significance to reveal the Chinese theory intension of "homotherapy for heteropathy ".

Inclusion Criteria:

1. It meets the diagnostic criteria of diarrhea-predominant irritable boewl syndrome and meets the diagnostic criteria for damp-heat syndrome.
2. Age between 18 and 70 years old.
3. Not taking antibiotics, steroids and other hormones, Chinese herbal preparations in the past week (including) Probiotics such as oral and intravenous), microecological preparations or yogurt.
4. The subject informed and voluntarily signed the informed consent form. ;
5. Have a certain reading ability

Exclusion Criteria:

1. Patients with severe organ, liver, kidney and other major organ diseases, hematopoietic system, nervous system or mental illness;
2. combined with other digestive systemic lesions (such as peptic ulcer), or systemic diseases affecting digestive tract motility (eg hyperthyroidism, diabetes);
3. Those who are or need to continue to use drugs that may affect gastrointestinal function (antidiarrheals, antidepressants, anxiolytics, intestinal flora regulators, antibiotics, etc.);
4. Those with a history of allergic reactions to related drugs and a history of severe food allergies.