Sulfonylureas

Sulfonylureas are a class of drugs commonly prescribed to patients with type 2 diabetes. The most commonly prescribed sulfonylureas today are glyburide, glipizide and glimepiride.

Although many new type 2 diabetes treatments are available, sulfonylureas remain the most popular today. This may be in part a function of physicians’ habits, but an important factor is their low cost. Many types of sulfonylureas are now generic and are among the cheapest medications available for the treatment of diabetes.

How Do Sulfonylureas Work?

Sulfonylureas stimulate the body to produce or secrete more insulin. Other beneficial effects of the sulfonylurea class of drugs include suppression of glucose production in the liver and enhancement of the body’s ability to dispose of excess glucose into fat and muscle tissue.

The clinical efficacy of sulfonylureas in patients with type 2 diabetes is related to the pre-treatment levels of fasting plasma glucose and HbA1c. The higher the fasting glucose level, the greater the effect will be. In patients with a pre-treatment glucose level of approximately 200 mg/dl, sulfonylureas typically will reduce glucose by 60-70 mg/dl and HbA1c by 1.5-2%.  A drawback of sulfonylureas is that, on average, they lose effectiveness for 44% of patients within six years from the beginning of their use. Some individual patients may have a more prolonged course of successful sulfonylurea treatment and others may need to add other diabetic drugs within less than six years. Failure occurs more rapidly in younger, more hyperglycemic individuals and in those with lower insulin secretion at the start of treatment.

Side Effects of Sulfonylureas

Hypoglycemia and weight gain are the two most frequent side effects of sulfonylureas.

An early study, the UGDP (University Group Diabetes Program), published in the 1970s, also raised the possibility that sulfonylureas might make heart disease worse. However, the large UKPDS study (UK Prospective Diabetes Study), found that sulfonylureas are no more likely to increase coronary artery disease than any of the other agents tested (insulin and metformin), so the jury is out with respect to heart disease. We do know, however, that sulfonylureas have little or no effect on blood lipid concentrations.

The use of sulfonylureas during pregnancy remains controversial.

Read About Other Type 2 Diabetes Treatments:

• Treatment of Type 2 Diabetes with Insulin
• Biguanides: Metformin
• Dopamine Agonist: Cycloset (Bromocriptine)
• Amylin Analog: Symlin (Pramlintide)

Reviewed by Dr. Mariela Glandt, Apr. 2013