Tobacco comes from the leaves of the tobacco plant (Nicotiana tabacum and Nicotiana rustica), which contain the stimulant drug nicotine. Stimulant drugs act on the central nervous system to speed up the messages sent between the brain and the body. The leaf of the tobacco plant is dried, cured and aged before having other ingredients added to manufacture a range of tobacco-based products. For example, cigarettes (including some herbal cigarettes), cigars, pipe tobacco, chewing tobacco, and wet and dry snuff.
There are more than 4000 chemicals in tobacco smoke. Many of these chemicals are poisonous and at least 43 of them are carcinogenic (cause cancer). The three major chemicals in tobacco smoke are:
- Nicotine the chemical on which smokers become dependent.
- Tar which is released when a cigarette burns.
- Carbon monoxide (CO) a colourless, odourless and very toxic gas that is taken up more readily by the lungs than oxygen. Smokers typically have high levels of CO in their blood.
Tar in cigarettes coats the lungs and can cause lung and throat cancer in smokers. It is also responsible for the yellow-brown staining on smokers' fingers and teeth.
Carbon monoxide in cigarettes robs the muscles, brain and blood of oxygen, making the whole body especially the heart work harder. Over time this causes airways to narrow and blood pressure to rise, and can lead to heart attack and stroke. High levels of CO, together with nicotine, increase the risk of heart disease, hardening of the arteries and other circulatory problems.
Soon after smoking tobacco, the following effects may be experienced:
- Initial stimulation, then reduction in brain and nervous system activity
- Enhanced alertness and concentration
- Mild euphoria
- Feelings of relaxation
- Increased blood pressure and heart rate
- Decreased blood flow to body extremities like the fingers and toes
- Dizziness, nausea, watery eyes and acid in the stomach
- Decreased appetite, taste and smell
Quitting tobacco is more effective if tailored to suit a person's circumstances.
- Going "cold turkey"
- Nicotine replacement therapy (such as transdermal patches, gum, lozenges, inhalers, nasal sprays and sublingual tablets)
- Other pharmacotherapies such as bupropion (Zyban SR)
- Individual counselling or advice
- Support groups
- Alternative therapies, such as acupuncture and hypnosis
Source of information: DrugInfo Clearinghouse Australian Drug Foundation
Get Help Now
000 Emergency Assistance
National emergency assistance number for ambulance, police and fire response.
The National Tobacco Campaign Helpline for those wanting to give up tobacco.131848
Find your local student support services, by selecting your state, and then the name of your university or TAFE.