Sibutramine offers three types of benefit in weight management: by enhancing weight loss, by improving weight maintenance and by reducing the comorbidities of obesity. The clinical effects of sibutramine are explained through its known mode of actionas a serotonin (5-HT) and noradrenaline reuptake inhibitor (SNRI). This dual mechanism of action results in two synergistic physiological effects — a reduction in energy intake and an increase in energy expenditure, which combine to promote and maintain weight loss.
First, sibutramine promotes satiety after eating. This leads to a reduced food intake and decreased tendency towards snacking. It is important to note that sibutramine does not induce, as a primary effect, a state of anorexia which can beunpleasant. Instead, it enhances and may extend satiety by inducing a feeling of fullness after eating. Studies in which patients have been asked to rate their feelings of satiety on a visual analogue scale (VAS) have shown that sibutramine-treated subjects achieve higher scores than untreated subjects. Eighteen clinical studies conducted with sibutramine assessed satiety using VAS and, despite these studies not being powered to detect secondary endpoints, data from nine of the 18 studies show a significant effect of sibutramine on satiety, food cravings, hunger and snacking.