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Information |
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Drug Groups
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approved; investigational |
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Description
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Ursodeoxycholic acid is an epimer of chenodeoxycholic acid (DB06777). It is a mammalian bile acid found first in the bear and is apparently either a precursor or a product of chenodeoxycholate. Its administration changes the composition of bile and may dissolve gallstones. It is used as a cholagogue and choleretic. [PubChem] |
| Indication |
The drug reduces cholesterol absorption and is used to dissolve (cholesterol) gallstones in patients who want an alternative to surgery. |
| Pharmacology |
Ursodiol (also known as ursodeoxycholic acid) is one of the secondary bile acids, which are metabolic byproducts of intestinal bacteria. Primary bile acids are produced by the liver and stored in the gall bladder. When secreted into the colon, primary bile acids can be metabolized into secondary bile acids by intestinal bacteria. Primary and secondary bile acids help the body digest fats. Ursodeoxycholic acid helps regulate cholesterol by reducing the rate at which the intestine absorbs cholesterol molecules while breaking up micelles containing cholesterol. Because of this property, ursodeoxycholic acid is used to treat gall stones non-surgically. |
| Toxicity |
Neither accidental nor intentional overdosing with ursodeoxycholic acid has been reported. Doses of ursodeoxycholic acid in the range of 16-20 mg/kg/day have been tolerated for 6-37 months without symptoms by 7 patients. The LD50 for ursodeoxycholic acid in rats is over 5000 mg/kg given over 7-10 days and over 7500 mg/kg for mice. The most likely manifestation of severe overdose with ursodeoxycholic acid would probably be diarrhea, which should be treated symptomatically. |
| Affected Organisms |
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Humans and other mammals |
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| Elimination |
Only small quantities of ursodiol appear in the systemic circulation and very small amounts are excreted into urine. Eighty percent of lithocholic acid formed in the small bowel is excreted in the feces, but the 20% that is absorbed is sulfated at the 3-hydroxyl group in the liver to relatively insoluble lithocholyl conjugates which are excreted into bile and lost in feces. |
| References |
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Akare S, Jean-Louis S, Chen W, Wood DJ, Powell AA, Martinez JD: Ursodeoxycholic acid modulates histone acetylation and induces differentiation and senescence. Int J Cancer. 2006 Dec 15;119(12):2958-69.
[Pubmed]
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Smith T, Befeler AS: High-dose ursodeoxycholic acid for the treatment of primary sclerosing cholangitis. Curr Gastroenterol Rep. 2007 Mar;9(1):54-9.
[Pubmed]
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Jackson H, Solaymani-Dodaran M, Card TR, Aithal GP, Logan R, West J: Influence of ursodeoxycholic acid on the mortality and malignancy associated with primary biliary cirrhosis: A population-based cohort study. Hepatology. 2007 Aug 8;46(4):1131-1137.
[Pubmed]
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| External Links |
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