A Medical Council member who is also a vice-president of the Hong Kong Medical Association is being investigated for alleged improper prescription of methadone. The Department of Health's pharmacy unit launched the investigation on Wednesday after a report in the Chinese-language magazine Eastweek detailed a sting operation on Dr Henry Yeung Chiu-fat, who has clinics in Chai Wan and Tsing Yi. Methadone is a synthetic drug used in the treatment of addiction to heroin and morphine. Dr Yeung, a paediatrician, has been vice-president of the 4,000-strong Hong Kong Medical Association for five years and is president of the 1,500-strong Hong Kong Doctors' Union. He was appointed to the Medical Council, the profession's disciplinary body, in January for a three-year term. He was also a Medical Council member between 1997 and last year. Legislator Dr Lo Wing-lok, who represents the medical sector and is president of the Hong Kong Medical Association, said yesterday he believed the alleged offence involving Dr Yeung was 'an isolated incident'. Guidelines for doctors on the proper prescription of controlled drugs were laid down in 1996, he said. 'I still believe that these particular guidelines are very effective,' he said. 'If there is any allegation, that must be an isolated incident.' Dr Lo said that while he did not keep methadone in his clinic, some doctors might stock up on it as a pain-reliever for terminally ill cancer patients, for instance. Asked why a paediatrician, who treats babies and children, might need to stock up on methadone, Dr Lo replied: 'If a doctor is working in a community, even if he or she is a paediatrician, he may from time to time encounter patients of other age groups.' The Medical Registration Ordinance requires that members of the Medical Council can only be removed from office if they are sentenced to a jail term, declared bankrupt or for health reasons. Dr Yeung, who has sat on two inquiry panels and attended nine policy meetings of the Medical Council, did not return calls yesterday. Tim Pang Hung-cheong, spokesman of the Patients' Rights Association, said the Medical Council and the Medical Association should ask Dr Yeung to step down while the investigation was under way. 'This will further put a question mark on the integrity of the Medical Council as a disciplinary body and guardian of moral standards of doctors,' Mr Pang said. 'As vice-president of the Medical Association, Dr Yeung is expected to have a higher level of moral standards.'