Clenbuterol, the substance taken by two British weightlifters, is licensed for treatment of asthma in Germany. It is banned by the IOC for two side-effects: it acts as a stimulant, masking fatigue and risking over-exertion and collapse; and it acts as an anabolic agent, enabling the body to work harder and recover more quickly, but also able to damage the liver.
Professor Stephen Smith, a clinical pharmacologist at St Thomas's Hospital in London, said however: 'I am sorry to say that the IOC is not terribly informed on medical pharmacological matters. For many of the drugs on its banned list there is not a shred of evidence that they have any performance-enhancing effect. Clenbuterol would only have a stimulant effect if it was taken in enormous amounts.'
The likelihood that it had any true anabolic effects was negligible, Professor Smith insisted.
Richard Nicholson, editor of the Bulletin of Medical Ethics, said the IOC's list of banned drugs, which has been adopted by the British Sports Council, was riddled with inconsistencies. 'These people lack expertise in pharmacology. They have been clearly told that the list is inconsistent and yet they have done nothing to improve it.'
Dr Nicholson said that the list included drugs which were improperly classified and others, administered only intravenously to very sick patients, which 'could not possibly be taken by athletes'.
David Cowan, director of the IOC-accredited drug-testing laboratory at King's College, London, insisted that the IOC included medical practitioners.