What Is the Difference Between Alli and Xenicol?

Alli is a popular over-the-counter weight-loss pill, the first approved by the Federal Drug Administration (FDA). It is manufactured by GlaxoSmithKline. Xenicol is a prescription weight-loss pill manufactured by Roche. They share the same active ingredient, orlistat.

Xenicol

• Xenicol contains 120 mg of orlistat per capsule and is given by doctors to those who require treatment of obesity to be supervised by a physician.

Alli

• Alli contains 60 mg orlistat and can be purchased at most major drug stores. The company offers online support through www.myalli.com. Alli's package contains diet and exercise advice similar to what a doctor would tell a patient taking Xenical.

Both Require Supplements

• Both pills reduce the body’s ability to absorb vitamins, including A, D, K and E. Roche and GlaxoSmithKline recommend taking a vitamin supplement while taking the pill.

Both Have Side Effects

• Xenicol and Alli have possible side effects of loose stools and gas with oily spotting. To reduce this, both manufacturers recommend eating less fat, eating healthier foods and beginning an exercise program.

Safety Issues

• In 2009 the FDA received reports of liver injury in people using orlistat and began a review. Sources such as MayoClinic.com claim that as of 2009, no definite association had been established between orlistat and the risk of liver injury.

Lack of Long-Term Studies

• Dr. Sidney Wolfe, director of the Health Research Group at Public Citizen (a public advocacy group), spoke against Alli due to studies that showed pre-cancerous lesions in the intestinal lining. These studies were on rats given excessive doses of orlistat. Pro-Alli and -Xenicol users claim that there have been no long-term human studies that show negative effects.