The mechanism by which colesevelam HCl lowers glucose is not known. Knowledge of the potential mechanism of action is important for defining the role of the drug among oral antidiabetic agents available for use in subjects with diabetes. The objective of this study is to provide insight into the mechanisms of action of colesevelam HCl in T2DM. The mechanisms of interest include hepatic insulin sensitivity, rate of appearance of exogenous glucose and changes in incretin hormone concentrations.