LuckyLut says:

Alli
alli™ is the only FDA approved, over-the-counter weight loss product. The alli program includes alli capsules and myalliplan, an individually tailored, online action plan to help you lose weight gradually.
What makes alli different? FDA approval and a sensible approach that focuses on your long-term success.
alli isn’t just another product for you to buy. alli is a pill with a plan. This program requires a commitment to living your life in a new way as you learn to change your eating and activity habits.
alli is not for everyone, but alli is an option. If you are ready to take responsibility, alli and your hard work can help increase your weight loss by 50%. That means if you could lose 10 pounds with dieting alone, you could lose 15 pounds working with alli.
To find out if you’re ready for alli, take the alli weight loss readiness quiz.
Change is challenging
What’s so hard about taking a pill and following a plan? If you’ve ever tried to lose weight before, you know the hurdles. We’ve all heard the same thing for years: Eating a balanced diet and getting regular exercise are the starting points for any weight loss program.
In theory, that makes sense. In reality, it’s hard to do. Lots of people start a diet on Monday and get off track by lunch. They set a goal to only eat 600 calories a day and plan to spend five days at the gym. But nobody can maintain that kind of regimen. And who wants to live like that? With alli, you have an option based on gradual and healthy progress.
How alli capsules work
First, let’s talk about the capsule. alli prevents your body from absorbing about a quarter of the fat you eat. Fat is more calorie-dense than carbs or protein. Just one gram of fat has more than double the calories of the same amount of protein or carbs. So if you eat a reduced-calorie, low-fat diet and use alli capsules, you can make a real difference in your weight as you limit the total number of calories that enter your system.
Using reference guides available in the alli starter pack and support online, you’ll learn how to plan meals that limit your fat intake, track your progress using alli weight loss resources, and get more physically active.
How myalliplan helps
alli capsules work in partnership with myalliplan, a plan of customized guidance designed specifically for use with alli. When you purchase alli, you can activate your free membership with myalliplan for access to special features, including:
a personal myalliplan homepage, where you can view your goals and progress, your latest steps, your meal plan, and more
interactive tools that help you discover hidden calories and fat in foods
an online journal, so you can record your eating and exercise habits
lessons from clinical experts in weight loss — people who know what you’re up against when you’ve had a stressful day or a strong craving
healthy and delicious recipes, smart meal plans, shopping lists, a dining out guide – the tools you need to guide your choices and gain results
Following a reduced-calorie, low-fat diet is a great way to start, but participating in myalliplan can give you the added direction and practical advice you need to make every step count. And support is available 24 hours a day.

mr.answe says:

It is called Alli. It actually is a otc version of a drug that is already FDA approved. This blocks dietary fat and causes it to be lost in the stool. The manufacturer recommends that you either wear dark pants, or bring a change of pants because a good chance that poop will be leaking out of you while you are doing things like grocery shopping or even at work giving that all important presentation.