1, immediately discontinue all antibacterial drugs. 2, supportive therapy and anti-shock can be input plasma, albumin or whole blood, timely intravenous replenishment of adequate amount of fluids and potassium salts, etc.. The amount of rehydration is decided according to the degree of water loss, or oral glucose saline to compensate for the loss of sodium chloride, correct electrolyte imbalance and metabolic acidosis. If there is hypotension, vasoactive drugs can be used on the basis of blood volume supplementation. 3, methotrexate is the first choice for the treatment of this disease, the general usage is 250mg, 3-4 times a day, oral 7-10 days, 95% of patients respond well to treatment, fever and diarrhea can be relieved 2 days after the drug, diarrhea generally disappears within a week, the treatment of 72 hours after the detection of toxin B in the feces. severe cases of frequent vomiting can be administered intravenous drip method, but the efficacy is significantly lower than the oral administration method. Alcohol should be prohibited during the drug administration. Vancomycin used to be the main drug for this disease, but the efficiency and recurrence rate of vancomycin is similar to that of methotrexate. Vancomycin is expensive and is no longer used as the first-line drug for this disease. Vancomycin is not absorbed orally, does not damage the kidneys, and can reach high concentrations in the intestine; intravenous medication has low intestinal concentrations and should not be used. In patients with side effects or relapse after methotrexate use, vancomycin treatment is available, and the general usage is 125-250mg orally 4 times a day for 7-10 days. 5.Bacillus peptide has antibacterial effect on gram-positive bacteria and can be used for this disease, the dose is 25,000 units, taken orally 4 times daily for 7-10 days, the symptom relief is the same as vancomycin, it is not as good as vancomycin in eliminating pathogenic bacteria in feces. Bacitracin has a high incidence of nephrotoxicity and ototoxicity should not be injected with the drug, but the oral method has not been found side effects. 6.Other treatment: 2~4g of bacteriophage, 3~4 times a day, 7~10 days in total. This drug can combine with the toxin, reduce the absorption of toxin and promote the absorption of bile salts at the end of the ileum to improve the symptoms of diarrhea. The application of specific antitoxin treatment has been reported abroad. To restore normal intestinal flora, light cases are allowed to recover on their own after stopping antibiotics. In severe cases, oral lactobacillus preparations (such as lactase raw), vitamin C and lactose, honey, maltose, etc. can be given to support E. coli; oral folic acid, vitamin B complex, glutamic acid and vitamin B12 can be given to support enterococci. In case of fulminant cases, if medical treatment is ineffective and the lesion is mainly in the colon, or if there is significant intestinal obstruction, toxic megacolon, or intestinal perforation, colonic resection or rerouting ileostomy can be considered.