Colestipol pharmacokinetics

Pharmacokinetics Cholestyramine and colestipol are taken orally. Because they are insoluble in water and are very large (molecular weights are greater than 106), they are neither absorbed nor metabolically altered by the intestine. Instead, they are totally excreted in the feces. 

A single-dose, crossover study in 6 healthy fasting subjects found that the simultaneous use of colestyramine 8 g modestly reduced the AUC of a single 400-mg oral dose of ibuprofen by 26% and reduced its maximum serum levels by 34%. The rate of absorption was also reduced. Conversely, colestipol 10 g had no significant effect on the pharmacokinetics of ibuprofen. ... 

The anticoagulant effects of phenprocoumon and warfarin can be reduced by colestyramine, especially if the coumarin is given at the same time. An isolated report describes unexpected sensitivity to warfarin in a patient taking colestyramine, which was attributed to a possible reduction in vitamin K absorption with colestyramine. Colestipol did not alter the absorption or effect of phenprocoumon or warfarin and colesevelam did not alter the pharmacokinetics of warfarin. 

Colestyramine does not alter the pharmacokinetics of clofibrate when both drugs are given at the same time. Similarly colestipol does not alter the pharmacokinetics of clofibrate or fenofibrate, and colesevelam does not alter the pharmacokinetics of fenofibrate. Colestipol can reduce the absorption of gemfibrozil if given at the same time, but not if administration is separated by 2 hours. A similar interaction occurs between bezafibrate and colestyramine... 

Over a 6-day period no clinically relevant changes in the pharmacokinetics of clofibrate occurred in24 healthy subjects, who were given daily doses of colestipol 10 g at the same time as clofibrate 500 mg. Colestyramine 4 g four times daily had no effect on the fasting plasma levels, urinary and faecal excretion, or the half-life of clofibrate in 6 patients taking 1 g of clofibrate twice daily. In this study, the morning and evening doses of colestyramine were taken at the same time as the clofibrate. ... 

DeSante KA, DiSante AR, Albert KS, Weber DJ, Welch RD, Vecchio TJ. The effect of colestipol hydrochloride on the bioavailabihty and pharmacokinetics of clofibrate. J Clin... 

Harvengt C, Desager JP. Lack of pharmacokinetic interaction of colestipol and fenofibrate in volunteers. Eur J Clin Pharmacol ( 9S0) 17, 459-63. 

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