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Medication in the Treatment of Obesity (cont.)


What Is the Treatment of Obesity?


The safest and most effective way to lose weight is a combination of eating less and increasing physical activity.

  • While there are many different methods for decreasing the amount of food you eat, the successful ones all have one thing in common: reducing calorie intake.

Physical activity

Physical activity helps you lose weight by burning calories.

  • It also may help you keep weight off once you lose it.
  • Many obese people think they cannot exercise, but everyday physical activities such as walking, climbing stairs, doing chores, and dancing can help you lose weight if done daily for at least 30 minutes.

Behavior modification

This is another name for changing your attitude toward food and exercise.

  • These changes promote new habits and attitudes that help you lose weight.
  • Many people find they cannot lose weight or keep it off unless they change these attitudes.
  • Behavioral-modification techniques are easy to learn and practice.
  • Most involve increasing your awareness of situations in which you overeat so that you can stop overeating.
  • Support groups are one form of behavioral therapy.


Some obese people have difficulty losing weight through diet and exercise alone.

  • If that is the case with you, see your health care professional. He or she may be able to suggest some new strategies that you haven't tried.
  • In some, but not all cases, your health care professional may suggest additional treatments to help you lose weight. Medication is by far the most widely used of these treatments.


Surgery for obesity, called bariatric surgery, alters the stomach or the intestines so that the person digests less food or is satisfied with less food.

  • These operations have improved over the years and are now considered a safe and acceptable way to help obese people control their weight.
  • However, all operations have risks, and for that reason, surgery is recommended only for morbidly obese people (BMI greater than 40), or obese people (BMI greater than 35) if the person has serious obesity-related medical problems).
  • Like all treatment for obesity, surgery is successful only if the person is committed to lifestyle changes and has a desire for better health.


Many dietary supplements make promises about weight loss. In fact, few if any of these have been shown to definitely help with weight loss.

  • In general, people who have lost weight while taking these supplements also have eaten less and increased their physical activity.
  • However, some of these are being studied to see whether they are safe and effective.

How Can Medication Help You Lose Weight?

With one exception, the medications used to treat obesity work by suppressing the appetite.

  • Appetite suppressants decrease appetite by increasing levels of serotonin or catecholamines, such as norepinephrine. Serotonin and catecholamines are brain chemicals that affect mood and appetite.
  • The exception, Xenical, works by disrupting lipase, the enzyme in the intestines that controls absorption of fats. It prevents digestion of about 30% of the fats eaten. These undigested fats are not absorbed, but excreted, thus lowering the calorie intake.

These medications work best if used in conjunction with lifestyle changes such as eating less and increasing physical activity. Research studies conducted in people with obesity all show that people who eat less, increase physical activity, and take medication lose considerably more weight than people who use medication without making lifestyle changes.

Like all drugs, those used to treat obesity may have powerful side effects and other undesirable risks.

  • Prescription weight-loss medications should be used only under the care of a medical professional and only by people who are at high risk of obesity-related health problems.
  • This usually means people with a BMI of 30 or greater or those with a BMI of 27 or greater who have other risk factors such as high blood pressure or high cholesterol.
  • These medications should not be used for relatively minor or cosmetic weight loss.

Some physicians have experimented with combining weight-loss drugs.

  • Some have combined a weight-loss drug with another type of drug such as a selective serotonin-reuptake inhibitor (SSRI), a class of antidepressants that includes fluoxetine (Prozac) and sertraline (Zoloft).
  • This is called "off label" use because these combinations have not been approved by the U.S. Food and Drug Administration (FDA) for obesity.
  • Little information is available about the safety or effectiveness of these combinations.

Traditional weight-loss medications were approved for only a few weeks or months of use. The newer medications now in use may be used for longer periods. These drugs are still being studied to see whether they have any long-term side effects.

What Are the Risks and Benefits of Weight-Loss Medications?

The possible benefits of these drugs in the short term include weight loss, which may lower the risk of some obesity-related health problems. Whether these drugs actually improve a person's health over the long term is not known.

The risks include the side effects, which vary from drug to drug (see next section).

  • Side effects are especially a concern in patients who may be healthy other than their obesity.
  • Other concerns include the potential for abuse of the drugs (all except Xenical are controlled substances).
  • People taking these drugs often find that their weight loss tapers off after four to six months. This is usually attributed to development of tolerance, in other words that the medication has reached its limit of effectiveness. The drugs are being studied to see if tolerance really does occur.

To ensure your safety, before you start taking one of these drugs, be sure to let your health care professional know if you have any of the following medical conditions:

Medically Reviewed by a Doctor on 11/21/2017
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