Ursodiol

Ursodeoxycholic acid

Clinical data
Trade names	Actigall, Udcasid, others
AHFS/Drugs.com	Monograph
MedlinePlus	a699047
License data	US DailyMed: 19396 US FDA: Ursodiol
Pregnancy category	AU: B3 US: B (No risk in non-human studies)
Routes of administration	oral
ATC code	A05AA02 (WHO)
Legal status
Legal status	AU: S4 (Prescription only) CA: ℞-only UK: POM (Prescription only) US: ℞-only
Identifiers
IUPAC name 3α,7β-dihydroxy-5β-cholan-24-oic acid OR (R)-4-((3R,5S,7S,8R,9S,10S,13R,14S,17R)-3,7-dihydroxy- 10,13-dimethylhexadecahydro- 1H-cyclopenta[a]phenanthren-17-yl)pentanoic acid
Synonyms	ursodeoxycholic acid, Actigall, Ursosan, Urso, Urso Forte
CAS Number	128-13-2 Y
PubChem CID	31401
IUPHAR/BPS	7104
DrugBank	DB01586 Y
ChemSpider	29131 Y
UNII	724L30Y2QR
KEGG	D00734 Y
ChEBI	CHEBI:9907 Y
ChEMBL	CHEMBL1551 Y
PDB ligand	IU5 (PDBe, RCSB PDB)
ECHA InfoCard	100.004.437
Chemical and physical data
Formula	C24H40O4
Molar mass	392.56 g/mol
3D model (Jmol)	Interactive image
Melting point	203 °C (397 °F)
SMILES O=C(O)CC[C@H]([C@H]1CC[C@@H]2[C@]1(C)CC[C@H]4[C@H]2[C@@H](O)C[C@@H]3C[C@H](O)CC[C@@]34C)C
InChI InChI=1S/C24H40O4/c1-14(4-7-21(27)28)17-5-6-18-22-19(9-11-24(17,18)3)23(2)10-8-16(25)12-15(23)13-20(22)26/h14-20,22,25-26H,4-13H2,1-3H3,(H,27,28)/t14-,15+,16-,17-,18+,19+,20+,22+,23+,24-/m1/s1 Y Key:RUDATBOHQWOJDD-UZVSRGJWSA-N Y

Ursodeoxycholic acid (INN, BAN and AAN), also known as ursodiol (USAN) and the abbreviation UDCA, from the root-word for bear urso, as bear bile contains the substance, 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 intestine, 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 (cholesterol) gallstones non-surgically. It is also used to relieve itching in pregnancy for some women who suffer obstetric cholestasis.

While some bile acids are known to be colon tumor promoters (e.g. deoxycholic acid), others such as ursodeoxycholic acid are thought to be chemopreventive, perhaps by inducing cellular differentiation and/or cellular senescence in colon epithelial cells.

It is believed to inhibit apoptosis.

Ursodeoxycholic acid has also been shown experimentally to suppress immune response such as immune cell phagocytosis. Prolonged exposure and/or increased quantities of systemic (throughout the body, not just in the digestive system) ursodeoxycholic acid can be toxic.

An incomplete list of the current uses is as follows: