• Oral Antidiabetic Drugs

1. Insulin (Humulin, Novolin): The hormone responsible for glucose utilization. It is effective in both types of diabetes, since, even in insulin resistance, some sensitivity remains and the condition can be treated with larger doses of insulin. Most insulins are now produced by recombinant DNA techniques, and are chemically identical to natural human insulin. Isophane insulin suspension, insulin zinc suspension, and other formulations are intended to extend the duration of insulin action, and permit glucose control over longer periods of time.
2. Sulfonylureas (chlorpropamide [Diabinese], tolazamide [Tolinase], glipizide [Glucotrol] and others) : act by increasing insulin release from the beta cells of the pancreas. Glimepiride (Amaryl), a member of this class, appears to have a useful secondary action in increasing insulin sensitivity in peripheral cells.
   lower plasma glucose primarily by stimulating insulin secretion.
3. Alpha glucosidase inhibitors (acarbose [Precose], miglitol [Glyset]) : inhibit the conversion of disaccharides and complex carbohydrates to glucose. This mechanism does not prevent conversion, but only delays it, reducing the peak blood glucose levels. Alpha-glucosidase inhibitors are useful for either monotherapy or in combination therapy with sulfonylureas or other hypoglycemic agents.
   delay carbohydrate digestion in the small intestine (by inhibiting enzymes which do this) and subsequent absorption, resulting in less postprandial elevation of blood glucose levels
4. Biguanides (Glucophage): augment muscular uptake of glucose
   is the only available member of the biguanide class. Metformin decreases hepatic (liver) glucose production, decreases intestinal absorption of glucose and increases peripheral glucose uptake and use. Metformin may be used as monotherapy (alone), or in combination therapy with a sulfonylurea.
   (e.g. Metformin) act by decreasing the liver's glucose production and may improve insulin sensitivity in those who lose weight.
5. Nonsulfonurea meglitinides: There are two members of the meglitinide class: repaglinide (Prandin) and nateglitinide (Starlix). The mechanism of action of the meglitinides is to stimulate insulin production. This activity is both dose dependent and dependent on the presence of glucose, so that the drugs have reduced effectiveness in the presence of low blood glucose levels. The meglitinides may be used alone, or in combination with metformin. The manufacturer warns that nateglitinide should not be used in combination with other drugs that enhance insulin secretion.
   (e.g. repaglinide) Similar in action to sulfonureas, but used in people with sufa sensitivity.
6. Thiazolidinediones: Rosiglitazone (Avandia) and pioglitazone (Actos) are members of the thiazolidinedione class. They act by both reducing glucose production in the liver, and increasing insulin dependent glucose uptake in muscle cells. They do not increase insulin production. These drugs may be used in combination with metformin or a sulfonylurea.
   (e.g. troglitazone ) are insulin-sensitizer drugs that improve insulin sensitivity in skeletal muscle and suppress hepatic glucose output. Only used in combination with other medications.

• Medications to manage elevated blood lipids or hypertension are also often used.
• Many of the above medications have significant side-effects and/or liver toxicity.