Nicotine: effects, mechanisms, and health implications

Nicotine & Caffeine

Compare and discuss the two somewhat contradictory views on the nature of nicotine dependence.

In the United States, dependence on nicotine is characterized by a recurrent pattern of the use of nicotine in such a manner that it may lead to social, occupational or medical problems. In addition, an individual is felt to be physiologically dependent on nicotine if the subject requires ever increasing levels of nicotine to achieve the same level of comfort, of if the individual experiences withdrawal symptoms within hours to days after t he last episode of use. (Typical withdrawal symptoms include tachycardia, tremor, agitation, and anxiety although in those with heavy or prolonged use there are cases of nausea, vomiting and transient visual, tactile or auditory hallucinations). In most cases, the subject will often use nicotine for a longer period than was originally intended and will attempt to discontinue or decrease use, often times unsuccessfully. Probably one of the greatest indicators of nicotine dependence is the continued use despite medical or personal consequences, i.e. A diagnosis of a nicotine related cancer, the loss of a job, etc. (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR). One school of thought relates nicotine dependence to the effect of nicotine exposure on the brain. It is easy to understand that early exposure activates nicotinic receptors. The theory that tolerance to levels of nicotine increases the number of binding sites in the brain is not necessarily true. Increased sensitivity to nicotine is not always associated with greater degree of use and resultant biochemical tolerance. In fact, in rodent models in which nicotine was provided at stable dosing, there was still evidence of increases in the number of nicotinic binding sites in the brain. This in turn gives pause to the theory that fluctuating levels of nicotine in the smoker contribute to new nicotinic receptor activation.

1b.

Describe your understanding of the major social, political, and economic ramifications associated with findings of deception perpetrated by the tobacco industry and cigarette manufacturers

In response to several lawsuits leveled against the tobacco industry, representatives from tobacco companies have testified that nicotine was not addictive. In 1994, Victor deNoble, a former tobacco company employee, became a speaker against the tobacco industry. deNoble, and documents obtained from major tobacco companies have indicated the companies knew that nicotine was not only addictive, but also associated with an increase in heart disease and cerebrovascular disease.

But the tobacco industry is a large employer in the southeastern United States, under significant attack since 1996 when several states won large settlements stating the companies knew nicotine was addictive and yet used deliberately deceptive tactics to cover their own findings, not only on addiction but also the effect of nicotine on the human body. While this is good for the health of the population at large, the United States receives large amounts of tax money from the tobacco industry. This and the strong tobacco lobby in Washington results in relatively small judgments actually being awarded to plaintiffs. While these judgments have resulted in a legal precedent, it is difficult for plaintiffs to continue to fight against the large tobacco industry defendants, especially with their far greater access to financial resource and tolerance for almost exhaustive appeals.

1c.

Would American society be better off if the tobacco industry was completely destroyed? Explain your viewpoint

While I do not agree with smoking, I feel that it is wrong to suggest the eradication of the tobacco industry wholesale. Plaintiffs in the cases brought forward in the early 1990s became smokers in an era before the Surgeon General's report on the health risks of smoking, and by the time all risks were known, many were hopelessly addicted. People of today know better, and are made aware of the risks of smoking. If people choose to smoke anyway, this is their right. To allow the destruction of the tobacco industry would essentially be the legislation of morality, and therefore a strike against basic tenets of the United States.

2a.

Describe the major concerns voiced about caffeinism and the potential toxicity of caffeine, including risks associated with its use during pregnancy. In your opinion, how serious are those risks?

When used injudiciously, caffeine has been noted to cause a wide variety of physical symptoms. Caffeinism describes the symptoms which occur when individuals who regularly drink large amounts of caffeine suddenly stop. While generally mild, symptoms have been reported to include muscle twitching and heart palpitations. In the DSM-IV, there are several disorders listed specifically associated with the use of caffeine.

Pregnant women are usually recommended to reduce their intake of caffeine, although the precise amount differs from study to study. In a study performed by Kaiser Permanente it was reported that the intake of 200 mg of caffeine per day was a significant risk for miscarriage. Another study, however, in the same year denied any association between risk of miscarriage and caffeine intake.

In light of the differing scientific evidence, one would probably be prudent to avoid or at least limit the use of caffeine in pregnancy, or even for general health. When any substance can be associated with a withdrawal syndrome, I believe it is better to be moderate in intake to avoid any untoward effects.

2c. Should children be restricted from caffeine use? Why? Is this a matter for government involvement? Parental guidance? Explain

Caffeine is the only psychoactive substance which is legally available to children.

It can be used in a therapeutic manner, such as improving breathing in premature infants, or to improve concentration in children with Attention Deficit Hyperactivity Disorder. However, all the changes in mood and physical activity which adults experience from caffeine are also seen in children. As children are not used as subjects in pharmacological studies, there is no "safe" threshold for caffeine use in a child. It would not seem prudent, however, to attempt to restrict children from caffeine, since this would also restrict children from eating chocolate. Without good scientific evidence linking caffeine to a significant health hazard and demonstration of a significant public health issue associated with childhood caffeine intake, one should attempt to instruct individuals, especially parents, on potential risks of caffeine use in children and hope common sense would intervene.

2d.

Discuss your own personal intake of caffeine, reporting on any noticeable effects resulting from a substantial increase and/or decrease in the amount consumed. How do any of your mood and/or behavioral changes correspond to those reported in your textbook readings? What recommendations would you make?