Abstract: HbA1c measurement is a critical component of diabetes management; however, a key limitation of HbA1c as a measure of glycemia is the lack of timeliness—it does not detect underlying blood glucose excursion levels in moderately controlled diabetic patients (HbA1c<8) as it is a measurement of mean glucose levels over the longer-term. HbA1c also averages both hypo- and hyperglycemia over two to three months; therefore, it does not adequately reflect improvements in post-prandial hyperglycemia. 1,5-AG is also a marker of glycemic control over a shorter one to two week timeframe, but with a different mechanism than HbA1c. Given the unique biological and physiological characteristics of 1,5-AG, it is sensitive to acute and transient episodes of hyper-glycemia and is, therefore, a better indicator of glucose excursions. Peptidyl diabetic drugs such as pramlintide and exenatide have unique mechanisms of action and the glycemic effects of these drugs are not adequately shown by HbA1c.