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Drug Saf. 2009;32(12):1141-6. doi: 10.2165/11316690-000000000-00000.

Safety and quality assessment of 175 illegal sexual enhancement products seized in red-light districts in Singapore.

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Applied Sciences Group, Pharmaceutical Division, Health Sciences Authority, Singapore.



In recent years, there has been increasing interest in the use of herbs and supplements as an alternative to drugs used for the treatment of erectile dysfunction, in order to enhance sexual performance. Over the years, adverse events associated with the consumption of natural health products for sexual enhancement and the treatment of erectile dysfunction have been reported.


The objective of this work was to assess the safety and quality of 175 sexual enhancement health products seized from makeshift stalls in red-light districts of Singapore.


Seven raids were conducted by the Health Sciences Authority, Singapore, in two red-light districts in February and March 2008. 175 sexual enhancement health products seized from makeshift stalls were extracted with methanol and screened for Western drug adulterants using high performance liquid chromatography and gas chromatography-mass spectrometry. The labels and claims of the products were also evaluated.


Of the 175 products evaluated, 134 (77%) were found to be adulterated with Western drugs or their analogues. Most of these 134 samples (123 [92%]) were found to be adulterated with sildenafil. The extent of adulteration of these illegal health products with Western drugs, including synthetic phosphodiesterase type 5 enzyme (PDE-5) inhibitors, and the risks of consuming such illegal sexual enhancement products are discussed in this study. Because of the scope of the raids, sildenafil was the most common adulterant found. In addition, some products were found to contain high contents of sildenafil (>100 mg) and high contents of the antidiabetic drug, glibenclamide (glyburide). The resultant severe hypoglycaemia has led to ten fatalities.


The presence of Western drug adulterants and their analogues in illegal sexual enhancement products seized from red-light districts in Singapore, and their often misleading labels and claims, put the health of consumers at risk. To safeguard public health, greater public awareness of the danger of consuming such illegal products and the lack of quality control of these illegal sexual enhancement health products is important.

[Indexed for MEDLINE]

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