Zyban Health Dictionary

The leaf of several species of nicotiana, especially of the American plant Nicotiana tabacum.

The smoking of tobacco is the most serious public-health hazard in Britain today. It causes 100,000 premature deaths a year in the United Kingdom alone. In addition to the deaths caused by cigarette smoking, it is also a major cause of disability and illness in the form of myocardial infarction (see HEART, DISEASES OF), PERIPHERAL VASCULAR DISEASE, and EMPHYSEMA. Tobacco-smoking is also a serious hazard to the FETUS if the mother smokes. Furthermore, passive smoking – inhalation of other people’s tobacco smoke – has been shown to be a health hazard to non-smokers.

Composition In addition to vegetable ?bre, tobacco leaves contain a large quantity of ash, the nature of this depending predominantly upon the minerals present in the ground where the tobacco plant has been grown. Of the organic constituents, the brown ?uid alkaloid known as NICOTINE is the most important. The nicotine content of di?erent tobacco varies, and the amount absorbed depends upon whether or not the smoker inhales. Nicotine is the substance that causes a person to become addicted to tobacco smoking (see DEPENDENCE).

Tobacco smoke also contains some 16 substances capable of inducing cancer in experimental animals. One of the most important of these is benzpyrene, a strongly carcinogenic hydrocarbon. As this is present in coal tar pitch, it is commonly referred to in this context as tar. Other constituents of tobacco smoke include pyridine, ammonia and carbon monoxide.

Nicotine addiction is a life-threatening but treatable disorder, and nicotine-replacement treatment is available on NHS prescription. This includes the provision of bupropion – trade name Zyban®. The availability of this drug – which should be used with caution as it has unwelcome side-effects in some people – and the introduction of specialist smoking-cessation services to provide behavioural support to people who wish to stop smoking should result in a reduction in tobacco-related diseases. Given the critical position of nicotine in leading people to become addicted to smoking, it is anomalous that there are no e?ective government regulations covering the sales of tobacco. Because it is not a food, tobacco is not regulated by the Food Standards Agency; it is not classi?ed as a drug so is not controlled by legislation on medicines. Furthermore, despite being a consumer product, tobacco is exempt from the Consumer Protection Act (1987) and other government safety regulations. So the NHS is left to try to ameliorate the serious health consequences – lung cancer, cardiovascular disease, peripheral vascular disease, chronic bronchitis, and emphysema – of a substance for which there are no e?ective preventive measures except the willpower of the individual smoker or non-smoker. (Escalating taxation of tobacco seems to have been circumvented as a deterrent by the rising incidence of smuggling cigarettes into Britain.)

Action on Smoking and Health (ASH) is a small charity founded by the Royal College of Physicians in 1971 that attempts to alert and inform the public to the dangers of smoking and to try to prevent the disability and death which it causes.... tobacco