Metformin (Glucophage®, Glucophage XR®) is the only biguanide medication currently available. It acts in several ways, improving the effectiveness of insulin receptors (known medically as decreasing insulin resistance), decreasing sugar (glucose) production by the liver, and decreasing sugar absorption from the diet.
Meglitinides are similar to sulfonylureas, in that they force the pancreas to produce more insulin. However, they are short-acting and are less likely to cause dangerously low blood sugar. They are usually taken before every meal. Meglitinides include:
These medications work mostly by decreasing insulin resistance and are therefore less likely to cause dangerously low blood sugar. These medications include:
These medications prevent the breakdown of sugar and carbohydrates in the digestive tract, slowing their absorption. These medications are used to decrease blood sugar levels after meals. These medications include:
Dipeptidyl Peptidase Inhibitors
This is a relatively new class of oral diabetes drugs. Currently, there are four medications available in the group -- alogliptin (Nesina®), linagliptin (Tradjenta®), sitagliptin (Januvia®), and saxagliptin (Onglyza®). These drugs increase incretin levels in the body. Incretin is a hormone that helps to control blood sugar.