Slowed gastric evacuation accounts for the reduction of food intake by anorectic drugs.

The effect of mazindol given orally on gastric emptying of a radiolabelled solid meal was examined in 10 obese females. The patients underwent the measurement of gastric emptying twice: 2 mg mazindol was compared with placebo according to a double-blind study protocol. Mazindol significantly delayed gastric emptying (P less than 0.02 for both the gastric half emptying time, t1/2, and emptying index, Ix). The inhibition of the late phase of gastric emptying by mazindol was reflected by a significant (P less than 0.05) decrease of the shape parameter S of the power-exponential fitted gastric emptying curves, as well as by the comparison of the amount of food retained within the stomach (P less than 0.05 at 80 min and P less than 0.02 at 90 min). Potential mechanisms and the meaning of the findings are discussed.