Michelle Durkin, BSc
According to the Addiction Research Foundation tobacco use is still considered Canada's greatest public health concern even though the percentage of cigarette smokers is declining. Approximately 35,000 Canadians die prematurely each year due to smoking.1 Despite the increased risk of heart disease, lung cancer, emphysema and other health problems, patients are reluctant to stop smoking and attempts to stop often fail. This is because of nicotine, a naturally occurring alkaloid. It can cause both a physical and psychological dependence that can be compared closely with addiction to substances such as heroin and cocaine.1
Nicotine in the Body
Nicotine is rapidly absorbed into the body through the respiratory tree, buccal membranes, as well as percutaneously. Once in the body, it will mimic the effects of acetylcholine at nicotinic receptors (see Figure 1). These receptors are found at autonomic ganglionic synapses of the sympathetic and parasympathetic branches of the nervous system as well as neuromuscular junctions. Due to the wide distribution of these receptors in the body, nicotine can illicit a wide variety of effects and can act as a stimulant or a depressant.
Nicotine Substitution Therapy
Although the majority of smokers want to reduce or stop smoking, attempts to do so often fail.1 It is the powerful addiction to nicotine that can make quitting so difficult.
