ursodeoxycholic acid




MacroPhar Lab
Full Prescribing Info
Ursodeoxycholic acid.
Each capsule contains Ursodeoxycholic acid 250 mg.
Pharmacology: Pharmacodynamics: Ursodeoxycholic acid, the 7-β-hydroxyepimer of chenodeoxycholic acid (chenodiol), is a naturally occurring, hydrophilic bile acid found in small quantities in normal human bile (normally about 5% of total bile acids) and in the bile of certain animals.
The exact mechanism of action(s) of ursodeoxycholic acid in the dissolution of gallstones has not been fully elucidated, but it has been suggested that the drug suppresses hepatic synthesis and secretion of cholesterol and inhibits intestinal absorption of cholesterol.
Despite aqueous insolubility of cholesterol, in the presence of dihydroxy bile acids cholesterol can be solubilized in aqueous media through the dispersion of cholesterol as liquid crystals or micelles.
Appear to have small inhibitory effect on synthesis and secretion of endogenous bile acids into bile, does not appear to affect secretion of phospholipids into bile.
Site of therapeutic action include the liver, bile and gut lumen.
In patients with gallstones, combined actions of ursodeoxycholic acid change the bile from cholesterol-precipitating to cholesterol-solubilizing, which results in dissolution of cholesterol stones.
Pharmacokinetics: About 90% of a therapeutic dose of ursodeoxychoiic acid is absorbed in the small bowel after oral administration. After absorption, ursodeoxycholic acid enters the portal vein and undergoes efficient extraction from portal blood by the liver (there is a large "first-pass" effect) where it is conjugated with either glycine or taurine and is then secreted into the hepatic bile ducts. Ursodeoxycholic acid in bile is concentrated in the gallbladder and expelled into the duodenum in gallbladder bile via the cystic and common ducts by gallbladder contractions provoked by physiologic responses to eating. Only small quantities of ursodeoxycholic acid appear in the systemic circulation and very small amounts are excreted into urine. The sites of the drug's therapeutic actions are in the liver, bile, and gut lumen. With repeated dosing, bile ursodeoxycholic acid concentrations reach steady state in about 3 weeks.
Beyond conjugation, ursodeoxycholic acid is not altered or catabolized appreciably by the liver or intestinal mucosa. Ursodeoxycholic acid can be both oxidized and reduced at the 7- carbon, yielding either 7-keto-lithocholic acid or lithocholic acid, respectively. Free ursodeoxycholic acid, 7-keto-lithocholic acid, and lithocholic acid are relatively insoluble in aqueous media and larger proportions of these compounds are lost from the distal gut into the feces. Reabsorbed free ursodeoxycholic acid is reconjugated by the liver. Eighty percent (80%) 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 insoluble lithocholyl conjugates that are excreted into bile and lost in feces.
Cholemax capsules are used for the treatment of dissolution of radiolucent cholesterol gallstones, less than 20 mm in diameter.
The prevention of gallstone formation in obese patients undergoing rapid weight loss.
Dosage/Direction for Use
Recommended Dose: Gallstone dissolution: 8-10 mg/kg/day in 2 or 3 divided doses.
Prevention of Gallstones: 300 mg twice daily.
Mode of Administration: Orally.
Symptoms: Neither accidental nor intentional overdosage with ursodeoxycholic acid has been reported. The most likely manifestation of severe overdose with ursodeoxycholic acid would likely be diarrhea.
Treatment: Should be treated symptomatically.
Hypersensitivity or intolerance to ursodeoxycholic acid, bile acid or any of the components of the formulations.
Do not use ursodeoxycholic acid for dissolution of calcified cholesterol stones, radiopaque stones, or radiolucent bile pigment stones.
Do not use in patients with compelling reasons for cholecystectomy including unremitting acute cholecystitis, cholangitis, biliary obstruction, gallstone pancreatitis, or biliary-GI fistula.
Special Precautions
Ursodeoxycholic acid has not been associated with the liver damage; however, measure AST and ALT at initiation of and during therapy as indicated by particular clinical circumstances.
Monitoring: perform ultrasound images of gall bladder at 6-month intervals for first year of therapy to monitor gallstone response. If partial stone dissolution is not seen by 12 months of therapy, likelihood of success is greatly reduced.
Use In Pregnancy & Lactation
Pregnancy: Category B.
For safety reasons, treatment should not be carried out during the first trimester of pregnancy. As with any drug, if you are pregnant seeks the advice of a health care professional before using this product.
Lactation: Since there are insufficient data on the passage of ursodeoxycholic acid into breast- milk, it must not be used during breast-feeding.
Adverse Reactions
Gallstone dissolution: Abdominal pain, viral infection, headache, dyspepsia, upper respiratory tract infection, nausea, sinusitis, constipation, vomiting, pharyngitis, arthralgia, flatulence, back pain, cough, bronchitis, urinary tract infection, arthritis, myalgia, allergy, cholecystitis, rhinitis, fatigue.
Prevention of gallstone formation: Constipation, diarrhea, headache, nausea, dizziness, vomiting, upper respiratory tract infection, back pain, viral infection, fatigue, influenza-like symptoms, abdominal pain, musculoskeletal pain, dysmenorrhea, alopecia, sinusitis, flatulence.
Drug Interactions
Antacids (Aluminum-containing): Decreased absorption of ursodeoxycholic acid.
Bile acid sequesterants: Decreased absorption of ursodeoxycholic acid. Administer bile acid sequestrants (cholestyramine, colestipol) at least 2 hours before or after ursodeoxycholic acid.
Clofibrate: Possible reduced efficacy of ursodeoxycholic acid because of increased hepatic cholesterol secretion caused by clofibrate (and possibly other antilipemic drugs).
Estrogen: Possible reduced efficacy of ursodeoxycholic acid because of increased hepatic cholesterol secretion caused by estrogen.
Hormonal contraceptives: Possible reduced efficacy of ursodeoxycholic acid because of increased hepatic cholesterol secretion caused by oral contraceptives.
Keep in tight container, store below 30°C.
ATC Classification
A05AA02 - ursodeoxycholic acid ; Belongs to the class of bile acids. Used in bile therapy.
Cap 250 mg (white, hard gelatin capsule No.0 containing white powder) x 10's, 10 x 10's.
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