What Are the Most Powerful Appetite Suppressants?

by admin on October 18, 2012

Last July, the FDA approved the first new prescription weight-loss drug in 13 years. Belviq, which sounds more like a brand of mineral water than a diet pill, has been OK’d for obese patients and for the severely overweight with at least one obesity-related condition, like hypertension or diabetes.

How does Belviq work?
The drug works by controlling appetite — specifically by activating brain receptors for serotonin, a neurotransmitter that triggers feelings of satiety and satisfaction. Serotonin is also involved in mood; many antidepressant drugs work by preventing the reuptake of serotonin and keeping brain receptors bathed in the chemical. Researchers at Arena say their drug is designed to seek out only the serotonin receptors that affect appetite.

The weight-loss benefits are extremely modest. Compared to placebo, over the course of a year of dieting and exercise, patients taking Belviq lost an average of 3 to 3.7 percentof their initial body weight. A 200-pound patient could expect to lose an extra 6-7 pounds on Belviq, but she would have to keep taking the drug for the rest of her life to keep it off. The manufacturers of Belviq recommend that patients stop taking the drug if they don’t lose at least 5 percent of their body weight in the first 12 weeks.

How effective is it?
According to clinical trial data submitted by Arena to the FDA, nearly half of dieters without Type 2 diabetes who used the medication lost at least 5% of their starting weight — or an average of 12 lbs. — over a year, compared with 23% of those taking a placebo. For best results, dieters are advised to use the medication together with a healthy diet and exercise program. The approved labeling for Belviq also recommends that people discontinue the drug if they fail to lose 5% of their body weight after 12 weeks; longer treatment is unlikely to lead to meaningful weight loss.

The FDA rejected Belviq in 2010 because of unanswered questions about cardiovascular side effects and the drug’s propensity to cause cancer in rats. To allay the FDA’s cardiovascular concerns, Belviq’s manufacturer, Arena Pharmaceuticals, sponsored huge trials in which thousands of patients taking Belviq, or a placebo, received regular echocardiograms to see if the drug was harming their valves. The FDA panel concluded Belviq was safe enough to go on the market, but recommended an extensive post-marketing study to rule out cardiovascular complications. Which is … comforting?

The FDA won’t require patients on Belviq to get regular echocardiograms, but Dr. Eric Felner, a member of the FDA advisory panel that approved the drug, told the panel that in his opinion, “If you’re going to put your patient on this medication, you need to see them somewhere along the lines of every two to three months and probably get an echocardiogram at least two or three times a year.”

Arena’s stock price has more than quadrupled based on rising expectations that the drug would be approved, and some analysts are predicting that Belviq could bring in a billion dollars a year. So, why all the excitement over a drug that produces less weight loss than a good behavior-modification program?

Some physicians hope that Belviq will be a safe replacement for fenfluramine, the “fen” in fen-phen. Fen-phen was a combination of the serotonin-booster fenfluramine and the stimulant phentermine. Neither drug produced much weight loss on its own, but combined they were superstars.

Fen-phen was a blockbuster. In 1996 alone, doctors wrote some 18 million prescriptions a month. This was the Holy Grail of long-term obesity treatment.

The risks of fen-phen, of course, didn’t become apparent until after the drug was on the market. The FDA belatedly estimated up to a third of patients using fenfluramine or dexfenfluramine developed heart valve damage. Fenfluramine was subsequently withdrawn from the market in 1997. Phentermine is only approved for short-term weight loss.

Belviq is supposed to be safer than fenfluramine because it acts on just one serotonin receptor found almost exclusively in the central nervous system, whereas fenfluramine stimulated serotonin activity indiscriminately, including serotonin receptors on the heart valves. Belviq has never been tested in combination with phentermine, but some weight loss doctors already have big plans for a fen-phen revival.

Why did it take so long to get a new weight-loss drug approved?
The history of diet pills has been plagued by safety problems. Since 1999, when the last prescription weight-loss medication, Xenical (orlistat), was given the green light, one weight loss drug, Meridia (sibutramine) was taken off the market when users began showing increased risk of heart problems, and two others, Belviq and Qnexa, were rejected by the FDA over safety concerns. Manipulating the body’s weight-controlling pathways can have long-term consequences on the heart and other metabolic systems, so drug developers have a high bar to clear to prove their compounds are safe.

“I know that some of you are afraid that the clinicians will combine [Belviq] with phentermine,” Dr. Ed Hendricks, a weight loss physician, and a member of the FDA advisory panel that approved Belviq, told the panel in May. “You have to remember that the motivation behind developing this drug was developing a replacement for fenfluramine that was safe.”

Hendricks went on to explain that if Qnexa, a weight-loss combination of phentermine and an anti-convulsant currently in the pipeline, is approved, many clinicians will consider thatde facto proof that phentermine is safe in long-term combination therapy and take it as a green light to prescribe a Belviq/phentermine cocktail. Hendricks didn’t mean this as a warning, but rather as something to look forward to.

Appetite suppressants work by tricking the body into thinking it isn’t hungry. Some appetite suppressants are available over the counter while others require a prescription. Doctors may recommend the use of weight-loss products for overweight people, particularly those who have certain conditions related to obesity, such as high blood pressure or diabetes.

When will Belviq and Qsymia be available?

Vivus says Qsymia should be available “in the fourth quarter of 2012,” which begins in September. But don’t look for it in your local pharmacy. Because women taking Qsymia must use birth control (see below) the drug will be sold only through “certified pharmacies.” These are likely to be major online pharmacies.

Because Belviq has a potential for abuse (see below), the U.S. Drug Enforcement Administration must rule on how to schedule the drug. That process probably began no later than last May. As this usually takes four to six months, Belviq should become available by early 2013. A quicker DEA ruling may speed the drug’s arrival.

Prescription Appetite Suppressants

Phentermine is the most often prescribed appetite suppressant, according to the Weight-control Information Network. Other choices include diethylpropion or phendimetrazine. In most cases, an appetite suppressant is only prescribed for a person with a body mass index of 30 or higher, or a person with a body mass index of 27 or higher with a health condition that is affected by obesity. Prescription appetite suppressants are typically prescribed for three to six weeks or up to a maximum of 12 weeks. They aren’t recommended to be used longer than that, because they can be habit-forming. These medications may cause sleeplessness, nervousness or abdominal discomfort.

OTC Appetite Suppressants

People who need to lose weight often wish for a magic pill to help them do so. Unfortunately, the effectiveness of over-the-counter diet pills is usually unproven or dangerous. Many appetite suppressants sold over the counter contain stimulants, which can lead to nervousness and restlessness. There are claims that certain herbal supplements can help with weight loss, such as green tea or acai berry, but these claims are controversial and inconclusive.

Foods That Suppress Appetite

In some ways, a healthy diet is the most powerful appetite suppressant of all. One of the easiest changes to make for a person who has a problem with over eating is to drink more water. What is perceived as hunger is often really thirst. A conscious effort to drink more water at the first sign of hunger can help tremendously in curbing the craving to overeat. Negative calorie foods, such as celery, spinach or cabbage require more calories to digest than are in the foods themselves. Snacking on these foods or high-fibre foods can help suppress appetite.

Considerations

Appetite suppressants are only meant to be used on a short-term basis, and should be used along with lifestyle changes, such as limiting portion size and becoming more active. Suppressing appetite is a small part of successful weight loss strategy. The more important part of losing weight is following a healthy diet and including exercise whenever possible.

Patients should remain skeptical. Off-label prescribing is a dirty little secret of the pharmaceutical industry. Pharmaceutical companies often seek approval for a narrow indication, knowing that doctors can and will prescribe the drug much more widely. Obesity medicine is full of frustrated doctors and desperate patients, demographics that have historically been easy pickings for snake oil salesmen. Our advice: Don’t buy the hype.

There are no magic pills for weight loss.

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