Medications

Issues and Options

The most important thing a person can do to combat obesity is to prevent obesity before it develops. But for those who need to treat or manage obesity, there are numerous options to consider.

Weight loss and weight management efforts to combat obesity require a balanced combination of behavioral change and medical intervention. Although consuming fewer calories and implementing a regular exercise routine are essential to the weight-loss process, some individuals dealing with obesity may need to incorporate prescription drug therapy into their weight loss program. Drug therapy is commonly recommended as a weight loss treatment option for persons with either a body mass index (BMI) of more than 30 who have no obesity-related conditions, or a BMI of more than 27 with two or more obesity-related conditions.

U.S. Food and Drug Administration (FDA)-Approved Medications

Medication for treating obesity, as prescribed and monitored by a physician, may be beneficial for some obese patients’ weight-loss regimen when combined with lifestyle, behavioral, and dietary modifications. There are currently two drug types – long term and short term – that are approved by the FDA for the long-term treatment of obesity.

Long-term Obesity Treatments

Sympathomimetic Drugs  – These weight loss drugs help treat obesity by suppressing one’s appetite through restricting nerve endings’ ability to pick up norepinephrine and serotonin. Sibutramine, the generic form of which is marketed as Meridia® in the U.S. and Reductil® abroad, is one such drug. It is manufactured by Abbott Laboratories.

Lipase Inhibitors – This class of weight loss drugs prevents the action of lipases (the enzymes that break down fat) produced in the pancreas. Orlistat, the generic form of which is marketed as Xenical® – manufactured by Roche Pharmaceuticals is the only weight loss drug approved to alter the way the body responds to fat intake. In February 2004, the FDA approved Xenical’s use for the treatment of obesity among adolescents, thereby making Xenical the first approved weight-loss treatment for children and adolescents in the U.S.

Short-term Obesity Treatments

Other FDA-approved weight loss prescription formulations include:

  • Bontril® (phendimetrazine tatrate), manufactured by Carnrick Pharmaceuticals;
  • Tenuate® (diethylpropion), manufactured by Aventis Pharmaceuticals;
  • Didrex® (benzphetamine), manufactured by Pharmacia Corporation/Pfizer; and
  • Lonamin®, Oby-Cap®, Fastin® and Adipex-P® (phentermine), manufactured by several pharmaceutical companies.

People treating obesity who have chronic conditions including heart disease, high blood pressure (including hypertension) or thyroid conditions should not use these weight loss drugs.

On the Medication Horizon – Looking Ahead

Clinical trials for several weight loss drugs that are not yet approved for the treatment of obesity are currently being conducted. For instance, Metformin® was recently found to produce a one to three kilogram weight loss over an average of 2.8 years in the randomized, double blind Diabetes Prevention Program (DPP).

Bupropion, which is marketed as Amfebutamone®, Wellbutrin® and Zyban®, is an anti-depressant and anti-smoking drug that produced significantly more weight loss in a randomized clinical trial than placebo during a one year examination.

Although it was found effective for significant weight loss, Topiramate®, a drug approved for treatment of epilepsy, also produced significant side effects during several trials of six to 12 months duration.

Zonisamide®, an anti-epileptic drug, also produced significant weight loss in a four-month randomized clinical trial.

Most recently, rimonabant administered to patients with dyslipidemia produced significant weight loss in patients, while decreasing triglyceride levels, increasing HDL-cholesterol (good cholesterol) levels, and reducing blood pressure. The trial, which spanned one year, also demonstrated rimonabant’s potential as an effective treatment to aid in smoking cessation. This drug has not yet been FDA-approved for any indications.

Over-the Counter (OTC) Weight Loss Treatments

Many OTC weight loss pills contain ephedrine, a compound that encourages weight loss by reducing the patient’s appetite and stimulating the body to produce more heat. One form of this weight loss drug is found in the Chinese plant ma huang and is sold in the U.S. without a doctor’s prescription.

There are many other herbal weight loss treatments containing ephedrine marketed to promote weight loss. However, ephedrine is not proven safe for the treatment of obesity. Although some preliminary studies have shown that taking supplements containing ephedrine was, at times, associated with weight loss, it is important to note that there are serious side effects associated with this weight loss treatment.

On February 6, 2004, the FDA published a regulation prohibiting the sale of weight loss supplements containing ephedrine. This prohibition took affect April 12, 2004. The Endocrine Society supports this regulation. Individuals are strongly advised to consult with a physician before taking any OTC product for weight loss.

Other OTC weight loss pills, including Dexatrim® and Acutrim®, are now ephedrine free. Although these products could be used in the treatment of obesity, and claim to help weight loss by boosting energy levels and stimulating metabolism, there are no published peer-reviewed studies to support these weight loss claims.