Possible thermogenesis with dexfenfluramine.

Fifty obese patients with a body mass index greater than 25 kg/m2 were randomized into 3 groups: control (C = 19), placebo (P = 18) and dexfenfluramine (D = 18). A behavioral modification program which included eating habits, exercise, attitudes, social relationships and six steps to lifetime weight control was taught every week. All patients strictly followed the food manual and recorded their behavior, physical activity and food intake every day through 12 weeks. Placebo and dexfenfluramine 30 mg/day were given in a double blind placebo controlled study. The results showed that all 3 groups had significant decreases in rest times and increased activity times (p < 0.05) and significant reductions of the average total daily energy, carbohydrate and fat intake (p < 0.05). They all lost weight. Mean +/- SEM cumulative weight loss was 8.3 +/- 0.7 kg in group D, 3.3 +/- 1 kg, in group P and 2.9 +/- 0.7 kg, in group C. The mean additional weight loss of 5 kg, and 5.4 kg seen with dexfenfluramine being highly significant (p < 0.001) from group P and C most likely due to increased thermogenesis. Significant (p < 0.05) and gradual reduction of biceps, triceps skinfold and per cent body fat were constantly observed only in the dexfenfluramine group. There were no significant differences among the 3 groups regarding blood pressure, heart rate, hematologic, lipids and biochemical profiles.