Information about Colestipol
Colestipol is a nonabsorbed bile acid sequestrant that is used a therapy of hyperlipidemia and for the pruritus of chronic liver disease and biliary obstruction. Colestipol has not been associated with clinically apparent liver injury.
Mechanism of action of Colestipol
Colestipol (koe les' ti pol) is a large, highly positively charged anion exchange resin that binds to negatively charged anions such as bile acids (as well as other organic compounds and some medications). The binding of bile acids to colestipol creates an insoluble compound that cannot be reabsorbed and is thus excreted in the feces. Bile acids ordinarily undergo extensive (>95%) enterohepatic recirculation, being secreted in bile, acting as fat solubilizing compounds in the upper intestine, and then being reabsorbed in the distal small bowel. Chronic loss of bile acids from colestipol use results in a contraction of the total bile acid pool. The liver compensates for this decrease by increasing bile acid synthesis, which directly competes with cholesterol synthesis resulting in a decrease in serum levels of cholesterol. Some of the decrease in serum cholesterol may also result from inhibition of fat absorption by the binding of bile acids to colestipol. Colestipol
FDA approval information for Colestipol
Colestipol was approved for use in the United States in 1977 and is one of the oldest and safest cholesterol lowering agents, but it is currently used largely as an adjunctive therapy when statins or other lipid lowering agents result in an inadequate decrease in cholesterol levels. Colestipol is used off-label to reduce the pruritus of chronic liver disease probably as a result of binding the “pruritogen” in the intestine (which is either a bile acid or an organic anion like a bile acid that undergoes enterohepatic circulation).
Dosage and administration for Colestipol
Colestipol is available in multiple generic forms and under the brand name of Colestid as a tablet of 2 grams or as powdered granules. The usual dose of colestipol tablets is 2 grams daily increasing to a maximum of 16 grams; whereas, that for the granules is 5 grams daily increasing to a maximum of 30 grams, based upon tolerance and effect. Colestipol is best given before meals and at bedtime. Other drugs should be given 1 hour before or 4 to 6 hours after colestipol.
Side effects of Colestipol
Colestipol granules can be unpalatable and difficult to swallow. Other side effects include abdominal discomfort, indigestion, nausea, flatuence and constipation.
Lipid lowering medications
- Niacin (Nicotinic Acid)