This drug, which has been in use since the 1950s, helps patients with type 2 diabetes make more insulin by stimulating the pancreas. Common examples of sulfonylureas (SUL-fah-nil-YOO-ree-ahs) include acetohexamide (brand name: Dymelor), chlorpropamide (Diabinese), glipizide (Glucotrol), glyburide (Diabeta, Glynase, Micronase), glimepiride (Amaryl), and tolbutamide (Orinase). These low-cost drugs are usually taken once or twice a day before meals.

Potential side effects: This class of drugs can cause blood glucose to dip too low and lead to hypoglycemia. People who are allergic to sulfa drugs should avoid these medications, and some people gain weight on these medicines.

If someone also takes nonsteroidal anti-inflammatory drugs (NSAIDs) or has reduced kidney or liver function, he may not be able to take sulfonylureas.

Potential drug interactions: Sulfonylureas and alcohol don't mix. Vomiting and flushing can result from combining the two. If a patient drinks and has been prescribed one of these medications, discuss this with his doctor.

Concerns specific to older adults: Due to the especially high risk of low blood sugar, chlorpropramide, a so-called first generation sulfonylurea, should never be taken by older adults, according to the American Geriatric Society Foundation for Health in Aging. In general, sulfonylureas isn't the drug of first choice for the elderly, since this age group is particularly hard hit by hypoglycemia. It's typically added when a third drug is needed after first trying Metformin and Actos, according to Rubin.

As a precaution when a sulfonylurea is introduced, doctors may prescribe it at half the usual dose and raise it slowly over a number of weeks. Or a physician may recommend using a shorter-acting sulfonylurea such as glimepiride or glipizide.