Objectives: To examine the rationale for long-term use of medications in the management of obesity, to provide an overview of published scientific information on their safety and efficacy, and to provide guidance to patients and practitioners regarding risks and benefits of treatment.
Data sources: Original reports and reviews obtained through electronic database searches on anorexiant drugs supplemented by a manual search of bibliographies.
Study selection: English-language articles that discussed the role of medications in the treatment of human obesity, and studies that evaluated their safety and efficacy for a minimum of 24 weeks.
Data extraction: Studies were reviewed by experts in the fields of nutrition, obesity, and eating disorders to evaluate study design and the validity of authors' conclusions.
Data synthesis: The long-term use of medications in the management of obesity is consistent with the current consensus that obesity responds poorly to short-term interventions. Net weight loss attributable to medication is modest, ranging from 2 to 10 kg, but patients taking active drug are more likely to lose 10% or more of initial body weight. Weight loss tends to reach a plateau by 6 months. Weight remains below baseline throughout treatment, although some studies show partial weight regain despite continued drug therapy. Most adverse effects are mild and self-limited, but rare serious outcomes have been reported.
Conclusions: Pharmacotherapy for obesity, when combined with appropriate behavioral approaches to change diet and physical activity, helps some obese patients lose weight and maintain weight loss for at least 1 year. There is little justification for the short-term use of anorexiant medications, but few studies have evaluated their safety and efficacy for more than 1 year. Until more data are available, pharmacotherapy cannot be recommended for routine use in obese individuals, although it may be helpful in carefully selected patients.