Table 2 Different formulations and the corresponding relevant characteristics of the oral drug metformin (information from [180])
Metformin formulation | Dose | Cmax (ng/ml) | tmax (h) | AUCmean (ng*h/ml) | Properties | Refs |
|---|---|---|---|---|---|---|
Immediate release (IR) | 1000Â mg bid | 1328 | 3.5 | 18,710 | Rapid gut absorption 90% absorption within 30Â min High systemic exposure GI side effects High systemic exposure | [180] |
Extended release (ER) [181] | 2000Â mg qd | 1688 | 5.1 | 16,990 | Two-phase approach tablet using polymers Prolonged gut absorption (duodenum and jejunum) 90% absorption within 10Â h | |
Delayed release (DR) [183] | 500Â mg bid/1000Â mg bid | 905/607 | 9/9 | 9010/6160 | Enteric coated (polymers) core tablet Release of metformin by pH of 6.5 (distal small intestine) Late gut absorption (ileum) Increased GLP-1 secretion Less systemic exposure | [10] |