Pharmacies are reporting brisk sales of Alli, which is sold by drug maker GlaxoSmithKline and is the first over-the-counter diet drug to win FDA approval. Unlike other prescription weight-loss drugs such as Meridia and the generic phentermine, Alli doesn't make you feel full, reduce cravings or curb your appetite. Instead, it prevents the body from breaking down and absorbing fat.
The active ingredient in Alli is orlistat, which is found in a higher dose in the prescription diet drug Xenical. Alli blocks about 25% of the fat you eat; Xenical blocks one-third of the fat you ingest. Alli, which is taken with meals, would prevent the body from absorbing about 4.75 fat grams or about 43 calories.
The downside of Alli is the fat it blocks can come out of your body in embarrassing ways. Glaxo said that drug can cause gas with oily discharge as well as frequent or loose stools. The site suggests it's probably a "smart idea" to wear dark pants and bring a change of clothes to work if you use Alli.
To avoid the side effects, Glaxo suggests limiting fat intake. Glaxo officials concede that many people would lose weight on their own with a diet that's moderate in fat, but that the pill helps them lose more weight.
If you'd lose 10 pounds on a diet, you'll lose 15 pounds by adding Alli to your diet.
If someone is consuming a diet already low in fat and high in carbohydrates, they likely won't get much benefit from Alli. However, doctors say most people are eating far more fat than they realize.
Orlistat has been used by an estimated 28 million people world-wide, and studied in 30,000 subjects in about 100 trials. But as with most diets, the dieters couldn't keep the weight off. During the second year of the study, the Orlistat users were given either the 120 mg dose or switched to 60 mg, the same dose in Alli.
Some dieters lost far more weight. About 50% of the people who use Orlistat lose at least 5% of their body weight. One out of five people who take the drug lose at least 10% of their body weight, according to Glaxo.
Even small amounts of weight loss offer clear-cut health benefits. It's not for the average person who wants to take it and doesn't want to change their diet. It's for someone who is committed to making a change in diet and lifestyle.
