MEDICATING THE OBESE PATIENT

CHALLENGES IN MEDICATING FOR OBESITY

Physicians face a challenge in safely navigating the regulatory terrain that exists regarding the use of existing pharmacologic agents for the treatment of obesity. Most of the currently available medications for use in obesity remain controlled substances. They are regulated at both the federal and state level. Physicians must be especially aware of the applicable state regulations because the state classification of an appetite suppressant may be even stricter than federal designation.

Once a

CHANGING ATTITUDES TOWARD MEDICATING FOR OBESITY

Increased understanding of the role of the autonomic nervous system, hormonal systems, food intake systems, and physical activity regulatory systems in effecting body weight and body composition leads to new approaches to treating the disorder of obesity. Knowledge of the mechanisms underlying obesity lends credibility to a pharmacologic approach.⁴ Recently, the widespread publicity surrounding discoveries in the genetics of obesity captured the attention of scientists and the public and

SELECTING PATIENTS FOR PHARMACOBEHAVIORAL THERAPY

Increased morbidity and mortality are well-known consequences of overweight. The data linking BMI to mortality as derived by insurance companies demonstrates a J-shaped relationship⁷ as shown in Figure 2. BMI is a commonly used expression of the relationship of height and weight and is derived from the following formula: Severe obesity, usually defined as a BMI of greater than 35, carries a high risk of morbidity and mortality.²⁶ As demonstrated by Figure 2, weight gain above this point

COMBINATION PHARMACEUTICAL THERAPY

In 1992 Weintraub and co-workers³⁰ demonstrated the feasibility of combining medications to take advantage of pharmacologic and clinical differences when they used fenfluramine and phentermine, a noradrenergic and a serotonergic

medication, in combination. The side-effect profiles of the drugs were complementary. Phentermine tended to cause insomnia, whereas fenfluramine tended to cause drowsiness. Phentermine tended to cause constipation, whereas fenfluramine tended to cause more frequent bowel

MEDICATIONS TO MAINTAIN WEIGHT LOSS FOLLOWING A MODIFIED FAST

Medically supervised very low-calorie diets of 400 to 800 kilocalories per day often use liquid diets and result in approximately 20 kg of weight loss in 12 to 16 weeks.²⁷ The problem with these diets is regain of weight within the first 1 or 2 years after treatment. Both positive¹² and negative¹ results have been reported in using medications to address the problem of weight regain in these patients. In one study¹ of 42 people on a very low-calorie diet, weight regain occurred despite

FUTURE DIRECTIONS

The future of medicating the obese patient holds both promise and challenges. There is much to learn. New pharmacologic approaches are exciting, and as we learn more about the mechanistic aspects of obesity and the regulation of body weight and body composition, new approaches for obesity will develop. There is continued interest in finding agents which increase thermogenesis or which are agonist or antagonists to the neuropeptides which regulate food intake or even specific macronutrient