Orlistat, brand name Xenical, a new drug for weight loss, has been approved by the Food and Drug Administration. The first of a new class of drugs called lipase inhibitors, Xenical does have some side effects that may be difficult to discuss in polite company.

Xenical's manufacturer, Hoffmann-La Roche, says it is different because it doesn't work in the brain to suppress the appetite as many other weight loss drugs do. Instead, Xenical works in the gastrointestinal tract. According to Roche, it prevents digestion of one-third of the fat a person eats. For example, if you eat 60 grams of fat, on Xenical, your body only digests 40 grams.

What happens to the other 20 grams? That may be where the side effects come in. The symptoms, according to Roche, are "mild and transient and may include oily spotting, flatulence with discharge, fecal urgency, fatty or oily stool, oily evacuation, increased defecation and fecal incontinence."

Roche also warns that Xenical not only blocks digestion of fat, but also fat-soluble vitamins: A (beta carotene), D, E and K. Therefore, if you take Xenical, it is advised to supplement your diet with these nutrients.

A Diabetes Care study reports that in clinical trials, people on orlistat lost an average of 6.2 percent of their body weight, while those on a placebo shed 4.3 percent on average. All had type 2 diabetes, and also experienced improved glycemic control. A study from The Journal of the American Medical Association gives similar conclusions about orlistat treatment.

Has To Be Taken Indefinitely

Priscilla Hollander, MD, PhD, of Baylor Medical Center in Dallas, co-conducted Xenical's clinical trials, and says that it was "tolerated very well," and that the unpleasant side effects "tend to attenuate over time."

Hollander also says you have to take Xenical over a long period of time for success. One of the reasons people need drugs to help lose weight, says Hollander, is that when people lose weight from restricting calories and exercising, many don't keep it up for long and the weight is gained back.

The same is true for Xenical. Those who take it gain weight when they stop using it.

"One has to continue Xenical indefinitely," reports Hollander.

For more information, find Xenical on the Internet at www.xenical.com or call (800) 746-5456.