Most of the slimming aids ordered by Swiss customers over the internet are positively harmful to health, according to a report released on Monday.

Swissmedic, the Swiss Agency for Therapeutic Products, issued a strong warning against such items after analysing 122 samples of illegally imported medicinal items seized by the customs authorities in 2010.

Nearly 90 per cent of the items tested contained substances known to be dangerous. They included Sibutramine, which can lead to heart and circulatory complications.

Some contained three times the recommended dose of Sibutramine, which  was withdrawn from the market more than a year ago. Taken in such large quantities, it can be life threatening.

Another dangerous substance found was Rimonabant, which regulatory authorities worldwide have also withdrawn from the market.

A third of the samples analysed were found to include chemical ingredients, despite being advertised as “purely herbal”. In many cases this was Sibutramine.

Swisssmedic says that worldwide more and more of such products are being ordered over the internet.

The agency cooperates with its counterparts internationally in attempts to track down the criminal organisations behind the trade.

Packages containing medicinal products are stopped at the Swiss borders. The import of large quantities of such products is illegal.

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