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Alli weight-loss pill: Does it work?

Is Alli the solution to your weight-loss woes? A Mayo Clinic specialist discusses the effectiveness of Alli, an over-the-counter weight-loss pill.

By Mayo Clinic staff

Photo of Donald Hensrud, M.D.
Donald Hensrud, M.D.

Alli (pronounced AL-eye) is meant for overweight adults who are struggling to shed excess pounds. With its easy access and weight-loss promises, is Alli your answer to losing weight permanently?

Here, Donald Hensrud, M.D., a preventive medicine and nutrition specialist at Mayo Clinic, Rochester, Minn., answers common questions about Alli.

What is Alli?

Alli is the reduced-strength version (60 milligrams vs. 120 milligrams) of orlistat (Xenical), a prescription drug to treat obesity. It's approved for over-the-counter sale to overweight adults 18 years and older. Alli is meant to be used in conjunction with a low-calorie, low-fat diet and regular exercise.

What are the concerns with Alli?

In 2009, the Food and Drug Administration (FDA) received reports of serious liver injury in people using orlistat and began a safety review. At this time, no definite association has been established between orlistat and the risk of liver injury. However, if you take Alli be sure to contact your doctor if you experience signs and symptoms, such as weakness or fatigue, fever, jaundice, or brown urine, which could indicate liver injury.

How does Alli work?

Alli promotes weight loss by decreasing absorption of fat by the intestines, which reduces the number of calories you absorb.

Lipase, an enzyme found in the digestive tract, helps break down dietary fat into smaller components, so it can be used or stored for energy. Alli works by disabling lipase, which prevents the enzyme from breaking down the fat while it's in your digestive tract. The undigested fat continues through the intestines and is eliminated through bowel movements.

Alli is taken with fat-containing meals, up to three times a day. Because of how Alli works, it's recommended that you eat no more than 15 grams of fat with each meal. Eating greater amounts of fat can cause unwanted effects, such as urgent bowel movements, diarrhea and gas with oily spotting.

How much weight could I lose using Alli?

Alli can help you lose weight, but the weight loss likely won't be great — perhaps just a few pounds more than you would lose with diet and exercise alone. Only a small number of studies have evaluated the effectiveness of Alli. And many of the weight-loss estimates are based on studies conducted on its prescription-strength counterpart, Xenical.

The average weight loss for prescription-strength Xenical is modest — about 5 to 7 pounds greater than diet and exercise alone after one year. So at half the strength, Alli could conceivably result in an average of 3 to 5 pounds lost in a year in addition to the approximately 8 pounds you could expect to lose from diet and exercise alone.

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References
  1. FDA approves orlistat for over-the-counter use. U.S. Food and Drug Administration. http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/2007/ucm108839.htm. Accessed Nov. 13, 2009.
  2. Snow V, et al. Pharmacologic and surgical management of obesity in primary care: A clinical practice guideline from the American College of Physicians. Annals of Internal Medicine. 2005;142:525.
  3. Anderson JW, et al. Low-dose orlistat effects on body weight of mildly to moderately overweight individuals: A 16-week, double-blind, placebo controlled trial. Annals of Pharmacotherapy. 2006;40:1717.
  4. Padwal RS. Drug treatments for obesity: Orlistat, sibutramine and rimonabant. Lancet. 2007;369:71.
  5. Alli — Introducing the only FDA-approved OTC weight loss product. Alli Web site for healthcare professionals. http://www.allihcp.com/IntroAlli_IntroAlli.aspx. Accessed Nov. 13, 2009.
  6. Alli side effects and frequently asked questions. MyAlli.com. http://myalli.com/whatisalli/commonquestions.aspx. Accessed Nov. 13, 2009.
  7. Early communication about an ongoing safety review — Orlistat (marketed as Alli and Xenical). U.S. Food and Drug Administration. http://www.fda.gov/Drugs/DrugSafety/PostmarketDrugSafetyInformationforPatientsandProviders/DrugSafetyInformationforHeathcareProfessionals/ucm179166.htm. Accessed Nov. 13, 2009.
  8. Hensrud D (expert opinion). Mayo Clinic, Rochester, Minn. Nov. 11, 2009.
  9. Anderson JW. Orlistat for the management of overweight individuals and obesity: A review of potential for the 60-mg, over-the-counter dosage. Expert Opinions in Pharmacothery. 2007;8:1733.
  10. Schwartz SM, et al. Compliance, behavior change, and weight loss with orlistat in an over-the-counter setting. Obesity. 2008;16:623.

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June 11, 2010

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