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Press Release

Public urged not to consume product with undeclared drug ingredients

4 Nov 2009

The Department of Health (DH) today (November 4) urged members of the public not to buy or use a product named "Zeng Da Yan Shi Wan" as it was found to contain an undeclared drug ingredient which may cause serious side effects.

The product was found during an investigation into a case of a 78-year-old man who was admitted to Queen Mary Hospital on September 26 for decreased general condition. Analysis showed that the product contained sildenafil, a drug used for treating male sexual dysfunction.

The spokesman said so far, there was no evidence to suggest that the patient's symptoms were related to the product.

Investigation into the source of the product is underway.

The side effects of sildenafil include low blood pressure, headache, vomiting, dizziness, and transient vision disturbances. It may interact with nitrates found in some prescription drugs (such as nitroglycerin for treatment of angina) and may lower blood pressure of patients to dangerous levels. Improper use of sildenafil may pose serious health risks, especially for patients with heart problems.

Under the Pharmacy and Poisons Ordinance of Hong Kong, products containing sildenafil must be registered before sale and can only be sold on a doctor's prescription and under supervision of a pharmacist.

Members of the public who have bought the product are advised not to take it. They should destroy and dispose of the products or submit them to the Department's Pharmaceutical Service at 3/F, Public Health Laboratory Centre, 382 Nam Cheong Street, Kowloon, during office hours.

"People who have sexual dysfunction should consult medical professionals," the spokesman said.

04 November 2009