EFFECT OF DEXFENFLURAMINE ON GASTRIC-EMPTYING OF A MIXED SOLID LIQUID MEAL IN OBESE SUBJECTS

Recent studies suggest that dexfenfluramine (D-fenfluramine), because of its pure serotonergic effect, may be a more potent anti-obesity agent, associated with fewer side-effects than the racemate dl-fenfluramine. The effect of dexfenfluramine on gastric emptying of a mixed solid and liquid meal was assessed with a double-isotope scintigraphic technique in eleven obese patients. Each subject took a placebo capsule on the morning and evening of the day before, and on the morning of the first gastric emptying measurement. Dexfenfluramine was then taken at a dose of 15 mg twice daily and gastric emptying measurements were performed at 5 and at 29 d after the initiation of active treatment. Dexfenfluramine significantly slowed gastric emptying of the solid meal at both 5 and 29 d when compared with the placebo (P < 0.05) and also delayed emptying of solid food from the proximal stomach (P < 0.01) but no significant effect on liquid emptying was observed. No significant side-effects were reported and there was a marginal weight loss (P < 0.005) during treatment. We conclude that inhibition of gastric emptying may contribute to the efficacy of dexfenfluramine in the treatment of obesity. © 1990, The Nutrition Society. All rights reserved.