Reduction of negative alliesthesia for sweet gustatory stimuli by cyproheptadine, a serotonin antagonist.

Cyproheptadine (CH) is a serotonin antagonist that increases food intake and body weight. In order to elucidate its mechanism of action on the control of food intake, hunger ratings, pleasure-displeasure to sweet gustatory stimuli and negative alliesthesia induced by a 50 g glucose load were compared in 14 healthy subjects after they had received a placebo or 16 mg of CH. Cyproheptadine did not affect the hunger rating, nor the affective rating in fasted subjects, but it reduced significantly the negative alimentary alliesthesia induced by the glucose load. It was concluded that CH increases food intake more by reducing satiation than by increasing hunger. This is in line with the anti-serotoninergic properties of CH, and the action of serotonin on the control of food intake.