Use and abuse of appetite-suppressant drugs in the treatment of obesity.

Most of the available appetite-suppressant drugs act on noradrenergic and possibly dopaminergic receptors to produce satiety. A smaller number increase excess neuronal serotonin levels by blocking serotonin reuptake or by increasing its release. All these drugs produce significantly greater weight loss than does placebo in most studies. Abuse is a problem with amphetamine, methamphetamine, and benzphetamine, whereas other drugs have minimal or no potential for abuse. Weight loss can be sustained for up to 36 months. Net weight loss, compared with placebo, ranges from 2 to 10 kg, and weight regain after terminating drug treatment proves that drugs do not work when not taken. The stigma of obesity, the public opprobrium toward obese persons, and regulatory rigidity have led to unjustified distrust in the potential of drug treatment for obesity.