Overview of Drugs & Surgeries for Treating Obesity

Wednesday, October 11, 2006 - 3:11pm

By John Messmer, MD

Achieving and maintaining weight loss takes time, determination, and effort. After trying numerous diets with little success, many people turn to more drastic weight loss methods, including prescription drugs and surgery, to help them with the process. Here are some of the more common methods and how they work.

Weight control drugs

1.   Amphetamines, "Fen-Phen" and Phenylpropanolamine to ease your hunger

For decades, amphetamine stimulants have been used to ease hunger. Unfortunately, they are addictive and have adverse effects on blood pressure and heart health. Less addictive drugs related to amphetamines have not been proven to be very effective. Moreover, they produce serious side effects. Two of these, fenfluramine and phenteramine (called "fen-phen" when used in combination), caused damage to heart valves in too many users. Phenylpropanolamine, a decongestant, was available over the counter for appetite suppression. Its effect was variable. A significant number of people developed a cerebral hemorrhage from its use; as a result it has been withdrawn from the market (even for treating nasal congestion).

2.   Sibutramine to lose weight

In recent years, sibutramine (Meridia), originally developed for depression, was found to lead to a 7% weight reduction in users. Its side effects are an increase in blood pressure and heart rate. For a person weighing 250 pounds who is 100 pounds overweight, a 7% loss means that he will lose about 18 pounds. Moreover, he must continue taking the medication indefinitely at a price of about $100 per month. Sibutramine's only real benefit is seen by people who have weight-related medical problems, such as diabetes, and who must lose weight using any possible means available.

3.   Orlistat to inhibit some fat absorption

Another medication, orlistat (Xenical), inhibits absorption of about one-third of a person's dietary fat. With this drug, a person can lose a total of 20 or more pounds at a cost of around $200 per month. In addition, orlistat also interferes with absorption of fat soluble vitamins. Unfortunately, the side effects of this feature have unpleasant results: If one eats too much fat while taking orlistat, oily stools may leak uncontrollably from the anus. When a person stops taking the medication, weight is regained unless a reduction in fat consumption is continued.

4.   Rimonabant to reduce your appetite

Soon a new obesity treatment, rimonabant, may be available. This drug blocks a brain cell receptor called a cannabinoid-1 receptor. This receptor is involved in addictive behaviors and body weight regulation. Blocking this receptor has been shown to reduce appetite, leading to weight loss by sustained calorie reduction. Coincidentally, it also reduces the desire for nicotine. As with other medical treatments, a person on this drug will probably need to take it indefinitely (or regain the weight).


Surgical weight loss procedures

Because medication has limited usefulness, surgical approaches have been developed. Surgical treatment accomplishes the same thing as dieting because a person is forced to eat less. There are two basic approaches: 1) bypassing the intestines to prevent food from being absorbed (gastric bypass), and 2) reducing the size of the stomach (commonly referred to as "stomach stapling"). These procedures are reserved for people with a body mass index (BMI) over 40, or for men who are 100 pounds overweight, or for women who are 80 pounds overweight.

1.   Gastric bypass for weight loss

During gastric bypass surgery, the lower part of the stomach is taken and attached to the small intestine further from the usual area. As a result, a portion of the absorptive area of the intestine is bypassed. In this way, some of the calories the person ingests will not be absorbed. Because this surgery interferes with the body's normal absorption process, medical problems can result from this surgery which will require long-term health management.

2.   Stomach stapling to control the amount you eat

This surgical option involves altering the stomach so it is smaller. When the stomach is smaller, a person can only eat a small amount, and it is possible to overcome this limitation by eating calorie dense foods like ice cream. Stomach reduction techniques are technically easier to do and can often be done through a laparoscope rather than by opening the abdomen. Since morbidly obese people are higher surgical risks, this is an advantage.

Note on liposuction as a weight loss method

Liposuction is not a viable option for weight loss. It can remove small areas of fat from around the buttocks or belly, but for substantial weight loss the dangers are too great. Even if it could be done, removal of body fat does not change the person's physiology, so medical problems are not helped simply by removing fat.


Surgical complications and criticisms

Complications from surgical treatment of weight loss are significant, ranging from infection to blood clots, bleeding and death. Despite these risks, surgical treatment can result in loss of 50% of starting body weight and help resolve obesity-related health problems, including diabetes, high blood pressure, high cholesterol and sleep apnea.

Some criticize these techniques because they basically only force people to eat less, costs in the range of $30,000, and require long term monitoring for complications. Supporters point to the high efficacy and beneficial effects on medical problems.

Diet, medication or surgery - which should I choose to lose weight

No matter how it gets done, the only way to achieve and maintain a normal weight is to change one's approach to food and consume less food/calories. Whether this goal is accomplished by following a balanced diet, by using medication, or by having surgery, is a matter of personal preference. When a person has repeatedly been unable to stay on a proper diet, medication or surgery may be the only way to treat weight related medical problems.