Obesity has become an epidemic in the United States and in many other
countries of the world. Obesity is a chronic disease, not a failure of
willpower. Diet, exercise, and behavioral modification of lifestyle a
re rarely successful over the long term. Medications have been used sp
aringly, because of concerns about addiction and ineffectiveness, but
used chronically, obesity drugs are effective. The two main categories
of obesity drugs are centrally active adrenergic and serotonergic age
nts. These drugs reduce appetite, enhance satiety, and increase energy
expenditure. Use of single agents produces modest weight loss and use
of combinations increases loss, but few patients reach their goal wei
ght. Co-morbidities associated with obesity resolve or are reduced in
severity with weight loss. Adverse events of major concern are changes
in brain biochemistry and primary pulmonary hypertension. Published g
uidelines for use of obesity medications recommend they be used only f
or medically significant obesity.