Drug alert: The Department of Health urges people not to buy or use slimming product Show Party, which can cause serious side effects.

The Department of Health urges people not to buy or use slimming product Show Party, which contains undeclared Western drug ingredients phenolphthalein and sibutramine which can cause serious side effects.

A 17-year-old girl suffered acute psychosis after taking the drug which was bought online. She was admitted to United Christian Hospital October 4. Her mental state remains unstable.

Phenolphthalein was once used for treating constipation but has been banned for its cancer-causing effect.

Sibutramine is a Western medicine used as an appetite suppressant. Its side effects include increased blood pressure and heart rate, psychosis and convulsions. People with heart problems should not take it.

Products with sibutramine must be registered before they can be sold in Hong Kong on a doctor's prescription and dispensed under a pharmacist's supervision.