OBJECTIVE: The aim of this study was to provide a comprehensive meta-analysis of randomized controlled clinical studies on the effects of sibutramine on weight loss and glycemic control in obese subjects with type 2 diabetes. RESEARCH DESIGN AND METHODS: Controlled clinical trials assessing the effect sizes of sibutramine on weight loss effects on glycemia in obese subjects with type 2 diabetes were identified and reviewed using the Cochrane Library, Medline, EMBASE, and a manual search. RESULTS: Eight placebo-controlled, double-blind, randomized trials of sibutramine were included. After sibutramine treatment, the decrease in body weight and waist circumference was significantly greater than in the placebo group. Fasting blood glucose and HbA(1c) significantly decreased after sibutramine treatment. Treatment benefits were seen in plasma triglycerides and HDL, without significant variations in serum total and LDL cholesterol. No differences in systolic blood pressure between the sibutramine and the placebo groups were seen, while recording of diastolic blood pressure and heart rate showed that sibutramine produced a small increase relative to placebo. CONCLUSIONS: A pharmacological approach in a weight management program for patients with type 2 diabetes may be helpful in glycemic control and in the management of other risk factors. Sibutramine may help improve glucose control because it is conducive to weight loss. The reviewed data on the effect of sibutramine further enforce the recommendations that weight management may be the most important therapeutic task for most obese subjects with type 2 diabetes.