DRUG CLASS AND MECHANISM: Ursodiol is a naturally-occurring bile acid that is made by the liver in humans and is secreted in small quantities in bile. It is used to dissolve and prevent cholesterol gallstones and to treat primary biliary cirrhosis, a disease of the liver. Ursodiol blocks the enzyme in the liver that produces cholesterol and thereby decreases production of cholesterol by the liver and the amount of cholesterol in bile. It also reduces the absorption of cholesterol from the intestine. By decreasing the concentration of cholesterol in bile, ursodiol prevents the formation and promotes the dissolution of cholesterol-containing gallstones. The mechanism by which it acts in primary biliary cirrhosis is not clear.
STORAGE: Store at room temperature, 15-30°C (59-86°F).
PRESCRIBED FOR: Ursodiol is used to prevent cholesterol gallstones from forming during rapid loss of weight. It also is used to dissolve cholesterol gallstones that do not contain calcium and are less than 2 cm in diameter. It does not dissolve gallstones that are composed of pigment rather than cholesterol. Ursodiol must be used for one or more years, and 50% of patients who have successful dissolution of their gallstones will have the gallstones return within five years. The likelihood of having successful dissolution of gallstones is low if partial dissolution is not seen within 12 months of starting treatment. Ursodiol also is used to treat primary biliary cirrhosis.
DOSING: The recommended dose for dissolving gallstones in adults is 8-10 mg/kg/day split into 2 or 3 doses. For treating primary biliary cirrhosis, the recommended dose is 13-15 mg/kg/day split into 4 doses. Ursodiol should be taken with meals.
DRUG INTERACTIONS: Aluminum containing antacids, cholestyramine and colestipol reduce the absorption of ursodiol and therefore reduce its action.
PREGNANCY: The are no adequate studies in pregnant women.
NURSING MOTHERS: It is not
known whether ursodiol is secreted in breast milk.
SIDE EFFECTS: The most common
side effects are rash, itching, nausea, vomiting, stomach pain, back pain, constipation and diarrhea.
Gallstones are stones that form when substances in the bile harden. Gallstones (formed in the gallbladder) can be as small as a grain of sand or as large as a golf ball. There can be just one large stone, hundreds of tiny stones, or any combination. The majority of gallstones do not cause symptoms.
Primary Biliary Cirrhosis is a chronic disease characterized by progressive inflammation and destruction of small bile ducts within the liver. The bile ducts transport bile from the liver to the intestine for the absorption of fat and elimination of waste products. The causes of Primary Biliary Cirrhosis may involve autoimmunity, infection, or genetic predisposition, acting alone or in combination. There are many medications and treatment options available for those with this and other associated diseases of Primary Biliary Cirrhosis.
Primary biliary cirrhosis (PBC) is a chronic (long duration) disease
characterized by progressive inflammation and destruction of the small bile
ducts within the liver. What are the bile ducts and what do they do? Lined with
cells named biliary epithelial cells, the bile ducts are tubules that make up a
plumbing system for the liver. The bile ducts along with the gallbladder are
part of what is called the biliary tract.
The plumbing system begins in the liver with very small caliber ducts that
connect to increasingly larger caliber ducts, like a tree in which twigs connect
to small branches that connect to larger branches. In fact, this system is often
referred to as the biliary tree. The large right and left bile ducts, still
within the liver, connect to an even larger common bile duct that runs outside
the liver to the small intestine just beyond the stomach. The common bile duct
connects by the cystic duct to the gallbladder....