Nicotine dependence potential

The various stimulants have no obvious chemical relationships and do not share primary neurochemical effects, despite their similar behavioral effects. Cocaines chemical strucmre does not resemble that of caffeine, nicotine, or amphetamine. Cocaine binds to the dopamine reuptake transporter in the central nervous system, effectively inhibiting dopamine reuptake. It has similar effects on the transporters that mediate norepinephrine and serotonin reuptake. As discussed later in this chapter in the section on neurochemical actions mediating stimulant reward, dopamine is very important in the reward system of the brain the increase of dopamine associated with use of cocaine probably accounts for the high dependence potential of the drug. 

The most direct way to help people manage the symptoms of nicotine dependence and withdrawal is therapeutic use of nicotine replacement therapy (NRT) (Fiore et al. 2000 Henningfleld 1995 American Psychiatric Association 1996). Nicotine has been shown to be the main active ingredient in tobacco that causes and sustains addiction to tobacco (US Department of Health and Human Services 1988). Laboratory research has demonstrated that animals (Goldberg et al. 1983) and humans (Henningfleld et al. 1983) who have been chronically exposed to nicotine or tobacco smoke will self-administer nicotine infusions. It should be noted that other constituents in tobacco, such as MAO inhibitors (Fowler et al. 1996a, b), may also play a role in tobacco dependence. The potential role of alkaloids other than nicotine has not been ruled out. This is consistent with the observations that what has been termed tobacco delivered nicotine is more addictive and toxic than formulations provided by nicotine replacement medications (Royal College of Physicians 2000). 

Henningfield JE, London ED, Jaffe JH (1987) Nicotine reward studies of abuse Uability and physical dependence potential. In Engel J, Orleand L (eds) Brain reward systems and abuse. Raven, New York, pp 147-164... 

The nicotine inhaler is likely to have a low abuse potential based on slower absorption, smaller fluctuations, and lower blood levels of nicotine when compared with cigarettes. Nicotine nasal spray has a dependence potential intermediate... 

The personal consequences of nicotine dependence are clearly the potentially life threatening illnesses that tobacco causes. Additional negative consequences become evident as tobacco use becomes less socially acceptable. Unlike the use of other recreational drugs or alcohol, tobacco use does not alter consciousness or cause escape from social responsibility. Therefore, until recently, smoking was regarded as a matter of personal choice. The links between second-hand smoke and disease in nonsmokers altered that view. Smokers often must face isolation and the outdoor elements to avoid exposing family, friends, and coworkers to second-hand smoke. Even then, they may face negative feedback from those around them. 

Autosomal dominant nocturnal frontal-lobe epilepsy (ADNFLE) is a form of partial epilepsy which is characterized by frontal-lobe motor seizures occurring during sleep (Philips et al., 1998). This disorder has been linked to a mutation in the channel-lining domain (M2) of the a 4 nicotinic receptor subunit with use-dependent potentiation of the electrophysiological response to nicotinic agonists (Lena and Changeux, 1998). If the symptoms of ADNFLE are secondary to overactivity of this receptor or unusual potentiation, then nicotinic antagonists such as mecamylamine may be helpful. 

Cannabis carries some potential for dependence and addiction. Compared to cocaine, heroin, alcohol, and nicotine, cannabis has lesser addictive potential and withdrawal effects, but some users do develop compulsive and maladaptive use patterns that require treatment (Taylor 1998). Individuals with underlying psychopathology or tendencies for substance abuse should be particularly leery of using cannabis in the interests of avoiding compulsive use patterns. 

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