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FDA Approves New Fat-Blocking Diet Pill That Targets Intestines

By Lauren Neergaard

The government approved a long-awaited pill Monday that sounds like a dieter’s dream: It blocks the body from absorbing almost a third of the fat a person eats.

Xenical is supposed to be only for obese people on strict diets.

Indeed, popping the pill before a big greasy cheeseburger and fries is almost certain to cause unpleasant side effects as the leftover fat exits the body.

But Xenical is the first-ever diet drug that works in the gut instead of targeting the brain to suppress appetite. So scientists expect that, gastrointestinal discomfort aside, it should be a safe drug--unlike two popular appetite suppressants that had to be banned in 1997.

Consequently, doctors are bracing for demand from people seeking a magic elixir for weight loss.

“This drug is not a magic bullet,” stressed Dr. Steven Heymsfeld of St. Luke’s-Roosevelt Hospital in New York, who helped research Xenical. “We don’t want it used just casually by itself without any diet, or just for cosmetic weight loss.”

Xenical, known chemically as orlistat, blocks intestinal enzymes. So instead of being stored on people’s hips, 30 percent of the fat they eat passes straight to the colon for excretion.

In studies, adding Xenical to a diet let people lose about 7 1/2 pounds more in a year than diet alone, the Food and Drug Administration said Monday.

Because of the way it works, Xenical can cause intestinal cramping, oily spotting, gas, fecal urgency and oily or loose stools. Some 27 percent of Xenical users had at least one episode, although the side effects tend to wane the longer people take the drug.

The more fat eaten, the more side effects. Thus, the FDA recommended that Xenical users get no more than 30 percent of their daily calories from fat, something they can calculate by reading food labels.

Xenical also decreases absorption of the important fat-soluble vitamins A, D, E and K, so users should take supplements two hours before or after swallowing Xenical.

Dieters take one Xenical capsule with each main meal, up to three daily.