There is disclosed a method for glycemic control of a patient having a disease selected from the group consisting of type 1 diabetes mellitus, type 2 diabetes mellitus, impaired glucose tolerance, hyperglycemia, and postprandial hyperglycemia, said method comprising administering to a patient in need thereof a pharmaceutical composition comprising an acetyl cholinesterase inhibitor compound. There is further disclosed a method for reducing HbA.sub.1C concentrations as a measure of glycemic control, comprising administering to a patient in need thereof a pharmaceutical composition comprising an acetyl cholinesterase inhibitor compound. Lastly, there is disclosed a pharmaceutical formulation for daily administration comprising an acetyl cholinesterase inhibitor, from about 5 mg to about 15 mg of loratadine and optionally from about 5 mg to about 16 mg of elemental zinc.