Colesevelam metabolism

Cholestyramine, colestipol, and colesevelam are not orally absorbed and are not metabolized by gastrointestinal enzymes. They are excreted in the feces as an insoluble complex with bile acids. Their onset of action occurs within 24 to 48 hours however, it may take up to 1 month to achieve peak response (7,15,20). 

Metabolism in a double-blind, placebo-controlled, parallel-group study with nearly 40 subjects with type 2 diabetes mellitus who were taking metformin monotiierapy, 38 patients were randomised to colesevelam or placebo colesevelam resulted in lowering of glucose and consequently, HbAlc concentrations [18]. 

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