Repaglinide
Brand Name Drug: Prandin in the U.S., GlucoNorm in Canada, NovoNorm elsewhere
Benzoic acid derivatives are the most recent addition to the list of treatment options for type 2 diabetes. In 1998, the FDA approved the first agent in this class, repaglinide. Benzoic acid derivatives are similar to sulfonylureas in that they are insulin secretagogues. However, they differ in that they bind to a different receptor on the beta cell membrane. Also, in contrast to sulfonylureas, benzoic acid derivatives do not cause direct exocytic insulin release in the absence of glucose stimulation.
The true benefit of these agents stems from the fact that they have a short duration of action. Repaglinide is administered just before the start of the meal and stimulates insulin secretion. However, the duration of action is much shorter than the sulfonylureas, and the main effect is to reduce postprandial hyperglycemia. Due to the short half-life, repaglinide is useful in patients who have erratic meal schedules.
The main advantage of repaglinide is the potential for decreased incidence of hypoglycemia, making it an effective agent in elderly patients and those with renal insufficiency or other predisposition to hypoglycemia. It is given only at the meal time in 1-mg and 2-mg tablets. Most patients are started on 0.5 mg prior to meals. It often is useful to initially monitor pre- and one-hour postprandial fingerstick glucoses to assess the effects of this agent.
Conclusion
Much of the benefit from tight control in patients with type 1 diabetes has now been extrapolated to the much larger group of patients with type 2 diabetes. Recent data have shown that tight control of type 2 diabetes is strongly associated with a decreased incidence and rate of progression of microvascular complications. Multiple new oral agents recendy have been developed for the treatment of this disorder. Effective use of these agents by physicians is imperative in controlling this disease and preventing or delaying acute and chronic complications in African Americans. It is important to remember that these new agents are relatively ineffective without proper dietary counseling and increased physical activity. In addition to glycemic control, treatment of hypertension and hyperlipidemia will also result in significant decreases in micro- and macrovascular disease in individuals with type 2 diabetes.
Comprehensive screening also is essential as it is estimated that 50% of Americans with the disease are unaware of their illness. The ADA now recommends testing of fasting glucose every three years for all adults >45 years. For higher risk groups, such as African Americans and those with a history of gestational diabetes, screening is recommended on a yearly basis. Those patients with a fasting glucose >126 mg/dL must receive proper dietary and exercise instruction as well as diabetic teaching about the importance of foot care and home glucose monitoring. These measures combined with the effective use of pharmacologic agents in those who fail conservative therapy will improve the control of the type 2 diabetes epidemic in the black community.