[Drug Name] Genetic Name: Chenodeoxycholic Acid Capsules 
　　　　　　English Name: Chenodeoxycholic Acid Capsules 
　　　　　　Chinese Pinyin: Equyangdansuan Jiaonang 

[Compositions] The main component of the medicine is chenodeoxycholic acid. 
　　Chemical name: 3α, 7α-dihydroxy-5β-cholanic acid. 
Chemical Structural Formula: 

　　　　　　　Molecular Formula: C24H40O4
　　Molecular Weight: 392.58 
[Description] The medicine is made of capsules with white or light-yellow crystalline powder; with exotic. 
[Indications] The medicine is used for cholesterol gallstones, as well as bile pigment stones and mixed stones. 
[Specification] 0.25g 
[Dosage and Administration] Orally, adjust according to the condition, generally 12 to 15 mg/kg daily on a body weight basis, slightly increased in obese individuals, up to 18 to 20 mg/kg daily.  Taken twice in divided doses with morning and evening meals or with milk. A treatment duration lasts more than 6 months. 
[Adverse Reactions] 
　　(1) The most commonly encountered side effect is diarrhea (30% to 50%), manifested as cramping pain in the lower abdomen, followed by watery stools, which are dose-related and disappear with dose reduction, and are tolerable in most patients if the dose is increased gradually. 
　　(2) Few patients (30%) may present transient reversible elevations of AST (SGOT). 
　　(3) Some patients may observe skin itching, dizziness, nausea, abdominal distension. 
[Contraindications] Patients with complete biliary obstruction and severe hepatic dysfunction are prohibited to take the medicine. 
[Precautions] 
　　(1) Dosage is cautious when the gallbladder is not functional. 
　　(2) Patients with cholesterol stones repeatedly onset biliary colic without improvement but even aggravated, or observe obvious stone calcification, the treatment should be discontinued and replaced by surgery. 
　　(3) The medicine takes a long time to take effect in dissolving of gallstones, usually half or even over a year. 
[Use in Pregnant and Lactating Women] 
　　Researches have shown that the medicine has potential liver toxicity to the fetus of rhesus monkeys, so avoid the use in pregnant women. Pregnancy can increase bile saturation and stone formation, which will affect the efficacy. 
[Pediatric Use] No reliable references, unknown. 
[Geriatric Use] No reliable references, unknown. 
[Drug Interactions] 
　　(1) Contraceptive pills can increase bile saturation, and other birth control measures should be taken as far as possible to avoid affecting the efficacy of treatment with the medicine. 
　　(2) Cholestyramine, colestipol and aluminum-based antacids bind to CDCA and reduce the medicine absorption, which should not be taken at the same time. 
[Overdosage] 
　　In case of overdosage, gastric lavage with not less than 1 liter of cholestyramine or activated charcoal (2 g per 100 mL of water), then immediately and orally taken 50 mL of oral aluminum hydroxide suspension. 
[Pharmacology and Toxicology] 
　　The main effect of chenodeoxycholic acid (CDCA) is to reduce the saturation of cholesterol in the bile. After taken CDCA (when CDCA accounts for 70% of the bile salt in the bile), the lipids in majority of patients return to microcolloidal state and the cholesterol is unsaturated, so that the cholesterol in the stones dissolves and falls off. High doses of CDCA (10 to 15 mg/kg daily) can inhibit the synthesis of cholesterol and increase the secretion of bile in patients with cholelithiasis, while the amount of bile salts and phospholipids secreted therein remains unchanged. When the dose is large, the incidence of diarrhea is high and it is toxic to the liver. 
[Pharmacokinetics] 
　　CDCA used in clinical practice is highly chemically pure unconjugated cholic acid with different crystalline forms. It dissolves quickly in the intestine, and the usual amount of 500 to 750 mg is almost completely absorbed whether it is taken on an empty stomach or with food. 
　　Small amount of the medicine is bound to plasma proteins and the free form remains low in peripheral blood. Part of it excreted into the intestinal lumen via the biliary tract and reabsorbed, forming the enterohepatic circulation. The liver was able to take up and remove efficiently with a first-pass effect of 62%. In the liver, CDCA binds to glycine or taurine and is excreted in the bile. Conjugated CDCA can be reabsorbed and is more readily removed by the liver. In the intestine, the conjugated form can be freed again and enter the newly ingested bile acid pool. The unabsorbed drug is excreted in the feces or converted to ursodeoxycholic acid (UDCA). However, most of the unabsorbed drug undergoes 7α-dehydroxylation by coliform bacteria and becomes lithocholic acid (LCA), which is the main metabolite after oral administration of CDCA. About one-fifth of the unabsorbed drug is absorbed by the terminal ileum and colon in the normal human body. The remaining formed bile salts are excreted in the feces. LCA is sulfated mainly in the liver and kidney, which makes it less toxic to the liver. Sulfates of LCA are poorly absorbed in the intestine and excreted in the feces, so sulfation prevents accumulation of LCA in the enterohepatic circulation. 
[Storage] In a shaded, cool and dry place (not exceeding 20℃). 
[Package] Aluminum-plastic plate, 12 capsules/plate × 2 plates/box 
[Shelf Life] 60 months. 
[Executive Standard] Chinese Pharmacopoeia (1995), Volume II. 
[Approval No.]: GYZZ H21022058 
[Manufacturer] 
　　Company Name: Panjin Hengchanglong Pharmaceutical Co., Ltd. 
　　Manufacturing Add.: Ping’an Town, Dawa County, Panjin City 
　　Post Code: 124207 
　　Phone No.: 0427-8854288 
　　Fax No.: 0427-6888502 
　　Website: www.hclyy.com.cn