The only FDA-approved weight loss medications are sibutramine (Meridia), orlistat (Xenical), and phentermine.

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The majority of these patients had underlying cardiovascular disease and were not eligible to receive sibutramine under the current labeling.

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Analysis of Payouji tea and Pai You Guo Slim capsules by the UK medicines watchdog revealed they contained diet drug sibutramine.

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Nor was Meridia (sibutramine), which Abbott Laboratories voluntarily withdrew from the market in October due to an increased risk for heart attack and stroke.

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In February, the ITF banned Czech Republic player Barbora Zahlavova Strycova for six months after she tested positive for the stimulant sibutramine at a tournament in October.

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Sibutramine was first approved as an anti-obesity drug in 1997, but data from recent studies suggests a higher rate of heart attacks and strokes among people taking it.

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The 26-year-old gave a positive test for sibutramine on October 16 at the Luxembourg Open as a result of taking weight-loss supplement ACAI Berry Thin but denied she had any intention to enhance her performance.

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In that same year, counterfeits of the weight-loss drug Alli sold over the Internet contained none of the active ingredient in the real drug but did contain sibutramine, the prescription-strength weight-loss drug Meridia, which has since been removed from the U.S. market because of concerns about cardiac side effects.

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After years of controversy, the Food and Drug Administration has asked Abbott Laboratories to yank the weight loss drug Meridia, generically known as sibutramine, from the market as a result of a large clinical trial that found the drug increased the rate of heart attack and stroke in patients at high cardiovascular risk.

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