WEDNESDAY, Feb. 7 (HealthDay News) -- The U.S. Food and Drug Administration has approved an over-the-counter version of orlistat, a prescription weight-loss drug available in the United States since 1999.

The OTC version, to be known as Alli, is recommended for overweight people ages 18 and older, along with a lower-calorie, low-fat diet and exercise program, the agency said. The higher-dose prescription version of the drug will remain available.

Orlistat, which works by decreasing the intestines' ability to absorb fat, is not recommended for people who cannot properly absorb food, or for those who are not overweight. The drug may also prevent the body from absorbing certain nutrients, so users should take a multivitamin at bedtime, the agency said.

A 60 mg. Alli capsule can be taken as often as three times daily at mealtimes.

Side effects may include loose stools and other changes in bowel habits, the FDA said. People who have had an organ transplant should not take OTC orlistat, since it may interact with other drugs they are taking. Also, anyone taking blood thinners, or being treated for diabetes or a thyroid condition should speak with a doctor before taking Alli, the agency said.

Alli is manufactured by GlaxoSmithKline, which in a statement said the drug "is the only FDA-approved weight-loss product available to consumers without a prescription."

More information

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