Free Lunch? Up-and-Coming Weight-Loss Drugs

By:
Nancy Snyderman, M.D.

rubberball

Eyeing a potential gold mine in the global obesity epidemic, pharmaceutical companies and universities have launched a massive drive to develop new and better diet pills. And I suspect over the next few years, we’ll have ripples of more and more diet drugs hitting the market. After all, the American public is overweight. More than two-thirds of us are obese, and we want something to fix it. Here’s a look at the next wave of diet drugs that may soon hit the market, as well as some off-label drugs used to treat obesity.

creative crop/getty images

Rimonabant

Available in Europe since mid- 2006 as Acomplia, rimonabant is currently under review by the FDA for prescription use here under the name Zimulti. It has been dubbed the ultimate diet pill and blockbuster drug by the press and medical community. Rimonabant works by blocking endocannabinoid receptors—present in the brain, where they affect cravings, and in fat cells, where they play a role in metabolism. These are the same receptors that bring on the “munchies” in marijuana smokers. Besides helping to control appetite, rimonabant plays a role in the breakdown of glucose and fat, which may explain why people taking the drug see improvement in a range of risk factors for heart disease and diabetes, namely their blood glucose and cholesterol readings, which can’t be explained by weight loss alone. Diabetics who took rimonabant for six months lost two and a half times more weight (15 pounds versus 6 pounds) than those taking a placebo, according to a study sponsored by Sanofi Aventis, the drug’s manufacturer. As for side effects, people who took rimonabant were slightly more likely to suffer anxiety and depression. Clinically obese people with low levels of high density lipoproteins (“good” cholesterol) and high levels of triglycerides, who have no history of anxiety or depression, are the best candidates for this drug.

d. klein/getty images

Lorcaserin

Currently in clinical trials, this drug works by activating a serotonin receptor in the brain that helps regulate appetite and metabolism. Early tests demonstrated that lorcaserin produced significant and progressive weight loss over a twelve-week period and was generally well tolerated at all doses. The drug, which hasn’t shown safety issues so far, has been under intense scrutiny by analysts who are concerned about its marketing viability, since lorcaserin is said to work similarly to now discontinued fen-phen, which caused heart problems. However, Arena Pharmaceuticals, the company that makes the drug, says lorcaserin is much more selective in the receptors it affects. In clinical trials, the drug had no apparent effects on heart valves or pulmonary artery pressure.

d. grill/getty images

Off-Label Weight-Loss Drugs

Many doctors believe it is sometimes appropriate to prescribe drugs for indications that have not been approved by the FDA—a practice known as off- label use. Off-label use is legal and, with important qualifications, generally embraced by physicians and other health- care providers, health-care institutions, insurers, pharmaceutical companies, and even the FDA. Before prescribing a drug for a use not on the approved label, doctors must be very well informed about the drug, its side effects, and the condition of their patients. Off-label use is not to be undertaken lightly or casually but with wisdom, firm scientific rationale, and sound medical evidence. 

So, in our unending quest for a miracle diet pill, Americans are being prescribed an array of prescription drugs approved by the FDA to treat a variety of illnesses. In most cases, the weight-loss side effect of these drugs was a serendipitous finding. People were prescribed the drug for an underlying medical problem, and weight loss was an observed side effect. But none of them has been approved as a diet drug.

The list includes drugs meant to treat attention-deficit hyperactivity disorder (Adderall), depression (Wellbutrin), epilepsy (Topamax and Zonegran), diabetes (Glucophage and Byetta), sleep disorders (Provigil), smoking (Zyban), and even opiate overdoses (Narcan). Often these drugs are used alone, but sometimes they’re taken in combination with each other or with popular weight- loss medications. 

g. doyle/getty images

While there is no hard data on the trend, doctors and patients say it has been increasing for years and that the drugs are being used by Americans, especially women, of all shapes and sizes. Here is where you have to be really careful. Asking your doctor to prescribe an off-label drug for weight loss is medical bungee jumping—and can be risky. I’ll use the drug Adderall as an example. Adderall, a stimulant originally marketed as a diet drug in the 1970s under a different name, is now a widely used prescription drug for the treatment of attention-deficit hyperactivity disorder (ADHD). Introduced in 1996 as a treatment for ADHD, Adderall stimulates neurotransmitters in the brain that are believed to improve a person’s ability to focus on a given task. One of its major side effects is weight loss, and according to media reports, Adderall is said to be the weight-loss agent of choice for everyone from soccer moms to Hollywood starlets, many of whom take it without a prescription. 

Because the drug is an amphetamine, it acts like speed when taken by people who are able to concentrate just fine on their own. The problem with taking a drug like this for a secondary use is that it has side effects that can go far beyond potential weight loss, even when taken as instructed: psychotic episodes, depression, and even serious heart problems. It shouldn’t be used casually or frivolously. 

It’s worth saying again: Weight is best managed by eating a sensible, moderate diet and getting plenty of exercise. If you’re thinking of taking any type of weight- loss drug, discuss your choices and the attendant risk factors with your doctor and decide what course of treatment—including diet and exercise—seems advisable in your situation. You want a program that will help you keep your weight off and not be just a quick fix. Given these drugs’ relatively modest effects, the secret of losing weight still lies in what goes into your mouth.

 

Excerpted from:
Diet Myths That Keep Us Fat by Nancy Snyderman, M.D.
© 2009, Crown.

 

 

Get more weight-loss truths.