When drug company Merck, maker of the arthritis medication Vioxx, announced a worldwide withdrawal of the drug on September 30, local pharmacies stopped selling and hospitals ceased prescribing it. This, despite the fact that, according to the Shanghai Drug Adverse Effects Monitoring Centre, there have never been any reports of adverse reactions related to the drug in Shanghai, which has a voluntary reporting policy.

Vioxx, a type of anti-arthritis drug called known as a "COX-2 inhibitor", is used by 2 million people worldwide.

Merck's decision to voluntarily withdraw the drug was based on new data from a three-year colon cancer trial.

The clinical study found that after months of treatment, there was a doubled risk for cardiovascular events, such as heart attacks and strokes, in patients taking 25 mg of Vioxx compared to those taking a placebo.

But according to Dr Du Wenmin, director of the centre,"Patients should not be too concerned about the recall issue, as the risk is small and there are a wide variety of alternative arthritis drugs to choose from. Patients taking Vioxx should stop using the drug and consult their physicians about switching to other drugs and possible adverse effects."

As a widespread chronic disease, arthritis is one of the most common debilitating illnesses. In China, about 10 per cent of the population suffers from the disease, and the incidence increases with age-over 80 per cent of senior citizens are arthritis victims.

But Vioxx is not the most popular arthritis drug in China. Many Chinese turn to cheaper domestic medicines or other alternative treatments.

"Vioxx is prescribed in major hospitals for about 10 to 30 per cent of arthritis patients, but it is less commonly prescribed in lower-level hospitals where many physicians are not familiar with the drug," said Dr Wu Desheng, chief of the Department of Orthopedics at Shanghai East Hospital, a major city hospital.

Vioxx is not included either on the national or municipal drug lists the medical insurance system follows, so its prescription rate is relatively low. Its price, as an imported arthritis drug, is nearly double that of domestically-made alternatives.

The State Food and Drug Administration has not issued an official ban or warning on Vioxx because withdrawal of the drug is a voluntary action of Merck, said Zhang Renwei, spokesman for the local Food and Drug Administration Bureau.

Chinese patients may post unused pills and packaging to Merck's Chinese joint-venture in Huangzhou, Zhejiang, for reimbursement, according to the company's website.

Other relevant information about Vioxx can be obtained at www.msdchina.com.cn, www.merck.com or www.vioxx.com.

Inquiries about reimbursement can also be made via a free hotline, 800-820-0188, after October 9.