Chapter 9 - Nicotine

Learning Outcomes

After reading through this chapter, you should be able to:

  • Discuss the effects of nicotine on alertness.
  • Discuss the effects of nicotine on sleep.
  • Name symptoms of nicotine withdrawal.

What is nicotine?

Nicotine is a stimulant found in the leaves of the tobacco plant. Tobacco has been smoked or chewed for centuries. Nicotine stimulates respiration and heart rate and depresses appetite by activating nicotinesensitive nerve receptors. In small doses, it wakes you up and gives you a high by exciting the central nervous system. It is highly addictive and the dangers to health have been well documented. Smoking cigarettes increases the chances of heart and lung disease and most smokers are less fit than non-smokers.

Cigarettes contain 1 to 20 mg of nicotine (depending on the brand and strength). The effect of nicotine mostly dissipates after 60 minutes. Nicotine readily diffuses through skin (patches), lungs (smoke), and mucous membranes such as the gums and the lining of the nose. The most common and quickest way for nicotine to enter the body is through the lungs. Nicotine moves to the small blood vessels, then to the brain, and finally to the rest of the body. Once it has reached the brain, it is responsible for the “good” feelings smokers experience. People usually keep smoking to maintain a constant level of nicotine in their bodies. The number of cigarettes it takes to do this varies from person to person because different people metabolize nicotine at different rates. People also have varying degrees of tolerance to and dependence on nicotine.

Nicotine withdrawal

Nicotine withdrawal can occur at night, making it difficult to fall asleep and stay asleep. Nicotine withdrawal may also contribute to nightmares and problems waking up in the morning. This is especially true for heavy smokers.

If you smoke, avoiding nicotine in the evening and at bedtime may help improve your sleep. If you stop smoking, you are likely to start sleeping better after 10 days without a cigarette. In heavy smokers, withdrawal symptoms can kick in 20-30 minutes after the last cigarette. Physical and mental withdrawal symptoms may include:

  • headaches
  • muscular aches
  • sore gums and tongue
  • impaired concentration
  • low blood pressure
  • lowered heart rate
  • feelings of stress or anxiety
  • depression and irritability

Physiological symptoms of withdrawal peak three to four days after quitting but can last up to 10 days. Sleep improves dramatically after withdrawal symptoms have passed.


checkmark Knowledge Check

  • Why might heavy smokers wake during the night?
  • Name two negative health effects caused by smoking.
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