Today, five classes of oral agents are available for treating Type 2 diabetes and at last count more than 40 formulations were in the market! And they keep increasing day by day.
Is any one oral agent better than the others?
More importantly, when treating a person with diabetes, how does one choose the type of drug to be used!
In order to make some sense of the plethora of oral agents available, it becomes essential to basically understand a few important points.
The first, and probably, the most important point is that none of the oral agents is insulin, no matter what name may be given to the drug by a company.
One should also understand that Type 2 diabetes is characterized by three basic abnormalities that contribute to the development of hyperglycemia:
- Impaired insulin secretion by the pancreas
- Peripheral insulin resistance mainly in the skeletal muscle
- Excessive glucose production by the liver
Type 2 patients that one sees in practice would have a combination of these three mechanisms which cause the high blood glucose levels. The problem is that the extent and severity of each of these mechanisms varies in different individuals, and the oral agent which would be most optimal for any patient would depend on which of these three mechanism plays a major role in their hyperglycemia.
Although there is no hard and fast rule for this, it is widely accepted that in lean type 2 patients, impaired insulin secretion is the predominant defect, while insulin resistance tends to be less severe than in the obese variety. Insulin resistance and hyperinsulinemia are the classic abnormalities of obese individuals with type 2 diabetes.
All the oral agents available do not have the same mechanism of action. Thus, one must know how a class of oral agent acts in order to choose the appropriate drug.