Alli is the best-selling diet pill in America. It was billed as a "wonder drug" when it was introduced last June. But now, Alli users are complaining the drug doesn't live up to all its hype. And worse yet, it causes some nasty side effects.
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Alli is the first FDA approved, over the counter diet drug. When it hit the shelves last summer, two million Alli starter kits sold within the first four months.
"I was in line, at the front door of Wal-Mart waiting for Wal-Mart to open when Alli was introduced," said Stephanie Henderson, a former Alli user.
Henderson has fought a life-long battle with her weight.
At 240 pounds, she thought Alli might do what dieting alone had not. On Alli, she lost ten pounds right away. Then her weight loss slowed, and the side effects began. They were so serious she ended up in the emergency room twice.
"I couldn't control my bowels. I was running to the bathroom, leaving meetings, being in the car, and literally stuck," she recalled.
Alli works by blocking fat absorption in the body. Its manufacturer, Glaxo Smith Kline, says if you control your fat intake, you're less likely to have the bothersome side effects.
"If you abuse the drug, if you abuse the fat intake that you're eating, you're going to see a treatment effect," Glaxo Smith Kline dietician Rebecca Reeves said.
Henderson stopped taking Alli after six weeks. Other users have posted similar complaints about Alli in an on-line support group.
One user wrote, "When they say to watch your fat intake - watch it. Otherwise you will pay."
Others say Alli didn't help them lose weight.
"I was on Alli for three weeks and followed the plan exactly," one post said. "The scale did not budge."
"People took it and had the same problems I did. It wasn't worth the expense and the trouble and the embarrassment to lose the weight," Henderson said.
But Glaxo-Smith-Kline and the FDA say that Alli, along with a sensible diet and exercise plan, can help users lose as much as 50 percent more weight than dieting alone.
And the manufacturer says that in recent trials, only around 5 percent of those who took the product dropped out of the program because of the side effects.
"It's an assist," Reeves said. "It's a way to help you give a little bit of an edge on losing weight."
Meanwhile, Henderson says she's through with diet pills, and is now trying to lose weight the old fashioned way.
"No late night snacks," she said. "Going to the gym three or four times a week."