Ursodeoxycholic acid (UDCA), also known as ursodiol, is a secondary bile acid, produced in humans and most other species from metabolism by intestinal bacteria. It is synthesized in the liver in some species, and was first identified in bile of bears of g + some more technical info UDCA is a 24 carbon bile acid with the chemical name 3alpha,7beta-dihydroxy-5beta-cholanic acid and a molecular weight of 392.57 g mol. It appears as a white to off-white crystalline powder, practically insoluble in water, freely soluble in ethanol and methanol, and sparingly soluble in acetone. The melting point range is typically reported near 203 to 207 degrees Celsius. Mechanistically UDCA is less hydrophobic than chenodeoxycholic acid and exerts choleretic and cytoprotective effects by displacing toxic bile acids in bile pools, stabilizing hepatocyte and cholangiocyte membranes, modulating bile acid transporters and signaling pathways that influence bile flow and inflammation. Pharmaceutical formulations are usually oral tablets or capsules containing the sodium or free acid form with typical dosing regimens individualized by indication and body weight.
Parent: Ursodeoxycholic acid
Parent: Ursodeoxycholic acid
Parent: Ursodeoxycholic acid
Parent: Ursodeoxycholic
Parent: Ursodeoxycholic Acid/ Chenodeoxycholic Acid
Parent: Ursodeoxycholic Acid/ Chenodeoxycholic Acid
Parent: Ursodeoxycholic
Parent: Ursodiol /Ursodeoxycholic Acid
Parent: Ursodeoxycholic acid
Parent: Ursodeoxycholic Acid
Parent: Ursodeoxycholic Acid
Parent: Ursodeoxycholic Acid
Typical quality specifications for active pharmaceutical ingredient batches include assay by validated HPLC showing UDCA content not less than 98.5 percent and not more than 101.0 percent. Individual related bile acid impurities such as chenodeoxycholic acid, deoxycholic acid and lithocholic acid are commonly limited to not more than 0.5 to 1.0 percent each, with total identified related compounds normally restricted to not more than 2.0 percent. Unspecified impurities are usually controlled to below 0.1 percent individually and below 0.5 percent total, consistent with ICH Q3A and Q3B principles. Residual solvents must comply with ICH Q3C class limits, for example ethanol NMT 5000 ppm where applicable. Heavy metals are typically specified as NMT 20 ppm and water content by KF titration is often specified NMT 0.5 percent, though exact limits should follow the product master file and pharmacopeial monograph for regulatory compliance.
UDCA is indicated clinically to improve bile flow and reduce cholestasis. Approved uses include medical therapy for primary biliary cholangitis and for the dissolution of certain radiolucent cholesterol gallstones in patients who are not good candidates for surgery. It is also used off label in various cholestatic liver conditions and to improve biochemical markers in selected liver diseases under physician supervision.
Evidence for UDCA in nonalcoholic fatty liver disease is mixed. Some trials show biochemical improvement in liver enzyme levels, but randomized controlled data do not consistently demonstrate significant benefit on liver histology or fibrosis. UDCA is not approved specifically for treatment of fatty liver and should not replace lifestyle interventions and guideline based therapies.
UDCA is usually taken orally with food to improve gastrointestinal tolerability and aid absorption. Dosing frequency depends on the indication and prescribed daily dose, commonly divided into two or three doses per day. Patients should follow their prescriber or product labeling for exact timing and dosing.
UDCA can dissolve small, radiolucent cholesterol gallstones that are well visualized by ultrasound in patients with a functioning gallbladder. Successful dissolution typically requires months to years of therapy and stones may recur after treatment stops. UDCA is not effective for calcified or pigment stones and is reserved for selected patients where surgery is contraindicated or declined.
