Ergot-derived dopamine D2 receptor agonists are the usual treatment of hyperprolactinemia and Parkinson's disease and recently bromocriptine has been approved for the treatment of type 2 diabetes. The aim of this study was the evaluation of short-term effect of cabergoline in poorly controlled diabetic patients with oral agent failure who refused insulin therapy.
Methods: This study was performed in 17 overweight women and men with type 2 diabetes with persistent hyperglycemia in spite of treatment with maximum dose of sulfonylurea, metformin and pioglitazone. 10 patients (group I) randomized to be treated with cabergoline 0.5 mg weekly for 3 months and 7 patients (group II) with placebo. Fasting and postprandial plasma glucose concentration and HbAlc measured in beginning and end of the study.
Results: FBS decreased from 210.70 +/- 21.29 to 144.90 +/- 26.56 mg/dl in cabergoline group whereas it decreased in placebo group insignificantly. Postprandial blood glucose decreased from 264.2 +/- 28 mg/dl to 203.6 +/- 34.34 mg/dl in cabergoline group whereas it increased in placebo group insignificantly. HbA1c decreased in cabergoline group from 8.48 +/- 0.44 to 7.7 +/- 0.11 whereas in control group it increased insignificantly from 8.7 +/- 0.33 to 8.8 +/- 0.16.
Conclusion: Cabergoline improves glycemic control in type 2 diabetic patients with oral agent failure. It reduces both fasting and postprandial plasma glucose levels and causes 0.45-1.11 reduction in HbA1c.