Even With Weight-Loss Drugs, Losing Pounds Isn't Easy

The National Institute of Health estimates 65 percent of Americans are overweight and 31 percent are obese. Out of the millions Americans who are overweight and go on a diet each year, many regain all or a part of the weight they loose within five years.

Consumers continue to look for a magic potion that will make them slim and trim with little or no effort.

"Many patients who are overweight come into the office looking for an easy way to lose weight," says Dennis A. Cardone, D.O., assistant professor at the University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School. "They think they can take a drug and not have to worry about changing their eating habits and exercising."

They are wrong.

Using prescription weight-loss drugs

According to the National Institutes of Health Weight-Control Information Network (WIN), weight-loss medications should be used only by patients who are at increased medical risk because of obesity.

Prescription weight-loss drugs are recommended in combination with a diet and exercise program for people who are obese (with a BMI of 30 or greater) or for those who are overweight (with a BMI of 27 to 29.9) and who suffer from two other risk factors for or diagnoses of chronic diseases such as high blood pressure, heart disease and diabetes, says Dr. Cardone. He generally recommends them to patients who are obese and have been unable to lose weight after making multiple attempts while under the supervision of a physician. A safe and reasonable goal for weight loss is 10 percent in six months.

How they work

Prescription weight-loss drugs work in one of two ways. They can suppress the appetite and increase metabolism by altering neurotransmitter uptake in the brain. Drugs that do this are: sibutramine, amphetamines and phentermine. A second type of drug reduces the body's ability to absorb fat. The drug orlistat works in this way. "It's important to take into consideration the patient's past medical history and the potential side effects and interactions of each drug," says Dr. Cardone.

Side effects of appetite suppressants include headache, constipation, back pain, insomnia, dry mouth, nervousness and upset stomach. Sibutramine, amphetamines and phentermine are contraindicated in the presence of hypertension, existing coronary heart disease and glaucoma.  Amphetamines should not be used in persons with hyperthyroidism.  The use of phentermine has, on rare occasions, been associated with the development of pulmonary hypertension, a fatal lung condition.

Side effects of drugs that affect how the body absorbs fat include oily spotting, gas (flatus) sometimes with discharge, urgency to have a bowel movement, fatty or oily stools and sometimes fecal incontinence.  Women may develop menstrual irregularities. People taking orlistat must take a supplemental multiple vitamin to prevent deficiencies of fat soluble vitamins.

Prescription weight-loss drugs are not magic potions. WIN recommends they be used in conjunction with behavioral treatment and nutritional counseling so you can make long-term changes in your diet and activity patterns. You'll also need to see your doctor regularly. Studies indicate if you don't lose four pounds in four weeks, it is unlikely the drug will contribute to significant weight loss.

What to consider

Before you and your doctor decide whether you should take weight-loss medications, consider that there is a potential for abuse or dependence -- many appetite suppressants are controlled substances. You could also develop a tolerance to the drug. And there are side effects. There are side effects. "The patient should be made aware of the possible side effects and be a part of the decision-making process," says Dr. Cardone.

Weight-loss drugs will not keep the weight off forever. "The safety of most weight loss drugs has only been studied over a short period of time," says Dr. Cardone. "And most studies have found that even with weight-loss drugs, most people will not be able to maintain weight loss over the long term. Drug therapy is only effective when used in conjunction with a structured diet and exercise program."