Alli – OTC Weight-Loss Medication

Alli™ is the first and only weight-loss medication to be approved for over-the-counter use in the United States. To be most effective, all weight-loss drugs should be an adjunct to a comprehensive weight-loss program.
Alli OTC Weight Loss Medication
Alli™ (pronounced AL-eye), a lower-dose version of the prescription drug Xenical™ (drug name - orlistat) is the first weight-loss medication to be approved for over-the-counter use in the United States. Xenical has been available by prescription since 1999.

Alli is provided in a 60 mg dose which is half the dosage of the 120 mg prescription of Xenical. At this lower dose, the amount of weight that is lost tends to be less than the 10% weight loss that is seen with the current prescription drugs.1,2 Like all prescription weight-loss drugs (sibutramine, phentermine and rimonabant), Alli should only be used to treat true obesity; it may also be considered for use for those who are overweight but have weight-related health complications.2 In addition, Alli (and all other weight-loss drugs) need to be taken indefinitely to sustain their effectiveness.

How Does Alli Work?
Alli is taken with meals and works in the intestines to block the absorption of about one-fourth of fat that is eaten. Alli is not absorbed into the body; it works in the GI tract and not on the central nervous system making it different than other obesity drugs. (For more information on the current obesity drugs, click here).

Side Effects
Alli is associated with unpleasant side effects, including oily diarrhea, rectal discharge, excess gas, and sudden loss of bowel control. Another reported side effect is reduced absorption of the fat-soluble vitamins (Vitamins A,D,E,K).

To minimize side effects, a low-fat diet and taking a daily multivitamin supplement in combination with the medication are recommended. Due to its risks and potential side effects, consider speaking with a physician first before taking it.

There is concern among some medical experts that the drug may be "misused" especially among adolescents and those with eating disorders. However, more information about its potential misuse is needed and will become available over time and as the drug becomes available on a more widespread basis.

Bottom Line - Like all weight-loss drugs, Alli needs to be an adjunct to a comprehensive weight-loss program that focuses on lifestyle modification. Research suggests that those who take obesity drugs have much greater success when also participating in a comprehensive weight-loss program than those who take the drug by itself.3

This content is reviewed regularly. Last updated June 20, 2012.

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1 Rossner S, Sjostrom L, Noack R, Meinders AE, Noseda G. Weight loss, weight maintenance, and improved cardiovascular risk factors after 2 years treatment with orlistat for obesity. European Orlistat Obesity Study Group.Obes Res. 2000 Jan;8(1):49-61.

2 Identification, Evaluation, and Treatment of Overweight and Obesity in Adults. NIH/NHLBI.

3 Wadden TA, Berkowitz RI, Womble LG, Sarwer DB, Phelan S, Cato RK, Hesson LA, Osei SY, Kaplan R, Stunkard AJ. Randomized trial of lifestyle modification and pharmacotherapy for obesity. N Engl J Med. 2005 Nov 17;353(20):2187-9.

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