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The Real Dangers of Weight-Loss Drugs

One-third of Americans are obese, and some doctors say more weight-loss medications are sorely needed. But Food and Drug Administration and numerous doctors question the drugs’ role in weight loss. And taking weight-loss supplements means that you might get potentially dangerous hidden ingredients.

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Sandra Stein of Queens, N.Y., constantly fought 10 pounds. She’d gain it, lose it and then gain it back.

After her doctor put her on an antidepressant and warned that it could cause weight gain, the extra 10 pounds became 40. Last year, she sought help from Dr. Louis Aronne, who treats obese patients and who also has conducted research for drug companies. At 5’2” and 165 pounds, Stein’s body mass index (BMI), which is a measure of weight relative to height that’s used to assess disease risk, was 30.2, which made her a candidate for prescription weight-loss medicine. (A BMI of 30 and above is considered obese and boosts the risk of heart disease and other ailments, according to National Institutes of Health [NIH].)

Aronne counseled Stein on diet and exercise but also suggested that she begin to take two prescription medications, which he prescribed for off-label use, or uses other than for what Food and Drug Administration approved them, to help her to shed pounds.

“Medicine helps people do better on a program of diet and exercise,” Aronne says. “It’s not instead of [diet and exercise], it’s in addition to.”

Seven months later, Stein, who’s 50-plus, was at her goal weight of 125, and she had a healthy BMI of 22.9. The weight-loss medicine made the difference, she says, because it helps her to control her portion sizes, she says.

Weight-loss treatments apparently never have been needed more. A third of U.S. adults are obese, according to National Center for Health Statistics, and another 35 percent are overweight. Doctors say that for many people, diet and exercise aren’t enough to bring their BMI down to a healthy range, which is below 25.

But the effectiveness of FDA-approved weight-loss drugs isn’t impressive. The drugs lead to an average weight loss of only about 10 pounds more than what would occur without the drugs, say U.S. Department of Health and Human Services and NIH. And some experts say the potential side effects of weight-loss drugs make the modest weight loss not worth the risk.

One such dissenter is Dr. David Katz, who is director and founder of Yale University Prevention Research Center and an advocate of obesity prevention. “I don’t think we have an obesity drug that is very effective, and I don’t think we are going to,” he says. For instance, Katz points out that some weight-loss drugs elevate blood pressure and that many obese people already have hypertension. “You can’t fix the problem with a drug that makes part of the problem worse,” he says.

Not on the Menu: Rejected or Withdrawn Prescription Weight-Loss Drugs

Not on the Menu: Rejected or Withdrawn Prescription Weight-Loss Drugs

FEDS UP. But other doctors who care for obese patients believe that obesity is a disease and that medications can help to fight it.

FDA has approved six weight-loss medications that are still on the market—benzphetamine, diethylpropion, orlistat, phendimetrazine, phentermine and—believe it or not—methamphetamine! (It’s prescribed under the name Desoxyn as an appetite suppressant/metabolism booster.) Altogether, those weight-loss medications are marketed under about 30 brand names. Costs vary greatly, from as little as $11 for a month’s supply to about $100. They might be covered by insurance, depending on your plan. Doctors and drug manufacturers concede that users must combine the medications with diet and exercise to attain the best results. But what’s really needed, they say, are more and better drugs.

The need for more choices is crucial, Aronne says, because one medication doesn’t work for everyone—just as is often the case for other conditions, such as diabetes. However, FDA is reluctant to approve more weight-loss drugs. It even rejected one this year that its advisory panel endorsed—a rare reversal.

FDA’s caution in approving weight-loss drugs is understandable, because the drugs sometimes are linked to dangerous side effects, which include increased blood pressure, heart palpitations, shortness of breath and chest pain. At least one drug, diethylpropion, has been linked to an increased risk of pulmonary hypertension, which is a rare and often fatal disorder.

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