Effect of dexfenfluramine on body weight, blood pressure, insulin resistance and serum cholesterol in obese individuals.

The effect of the serotonergic agent dexfenfluramine on weight loss, blood pressure, insulin sensitivity and serum lipid levels was determined in a 3-month randomised, double-blind, placebo controlled parallel design study in 50 obese subjects (body mass index 30-44 kg/m2). When compared with placebo treated patients, the dexfenfluramine group lost more weight (3.8 vs 1.1 kg, P < 0.01), had lower diastolic blood pressure (-5 vs -1.5 mmHg, P < 0.05), and lower cholesterol levels (-0.38 vs + 0.06mmol/l, P < 0.05), and showed improved insulin sensitivity (+ 11% vs + 4%, P < 0.03). Significant effects on blood pressure and insulin sensitivity were apparent after 1 week of treatment during which time weight did not change, suggesting a direct effect of the agent independent of weight loss. Dexfenfluramine thus improves a number of cardiovascular risk factors associated with obesity, with benefits additional to those achieved by weight reduction alone.