"What is it?"

Nicotine is a clear to pale yellow liquid that is naturally found in tobacco plants, tomato plants, and other plants in the Nightshade family. It was named after Jean Nicot, the French ambassador to Portugal in the 1560s. Nicot wrote and spoke much of the medicinal qualities of the plant following the discovery of its use among the tribes of North and Central America by early Western explorers.

Just like cocaine and heroin, nicotine is an addicting drug. When taken in small amounts, as in many tobacco products, it produces "pleasurable" feelings. It is absorbed through the lungs, the mucous membranes (the lining of nose and mouth) and the skin so may be smoked, chewed or applied in patches. Chewing tobacco must have flavorings added to make it attractive as tobacco tastes terrible. The most common and quickest way to get nicotine into the bloodstream is by smoking it. The lungs are lined by millions of tiny air sacs where the nicotine enters with the air and smoke inhaled. These air sacs have an enormous surface area - 90 times greater than that of the skin - and so the nicotine quickly passes into the blood. It reaches the brain about ten to fifteen seconds from the time it was inhaled.

Nicotine is an extremely toxic substance and is considered more additive than heroin. 20-100 mg of nicotine causes death depending on the size of the person or animal. Cigarettes contain 9-30 mg of nicotine depending on the type of cigarette; while a cigarette butt contains about 25% of the nicotine of the original cigarette despite its deceptively small amount of tobacco. Cigars can contain up to 40 mg. Chewing tobacco carries 6-8 mg per gram while the gum is 2-4 mg per piece and patches 8.3-114 mg. Smoking a cigarette yields only 0.5-2 mg of nicotine but eating one is another story as all of the nicotine becomes available for absorption into the body in the small intestine. However, one of the first things nicotine does in the body is to stimulate the vomit centre of the brain, which may save the patientís life if there is more cigarette material in the stomach. Nicotine is also sold commercially in the form of a pesticide - it kills things!

Nicotine affects the chemistry of the brain. It stimulates the release of a chemical messenger in the brain. This messenger is responsible for feelings of pleasure and temporarily increases mental alertness. This is why nicotine is put in the category of drugs called stimulants. A stimulant is a drug that produces a short-lived increase in the body's activity. The human brain reacts the same way to nicotine as it does to cocaine and heroin. They all cause "highs" to occur in the person using them. However a tolerance to these effects develops rapidly. Tolerance means that a smoker will need more and more of the drug to reach the same "high". Addiction may begin with someone's first experience with nicotine. People become dependent on the drug and suffer both physical and emotional withdrawal symptoms if they stop using it. Irritability occurs when a person tries to quit. Nicotine doesn't stay in the body for too long, lasting only 40 minutes to a couple of hours. This means that to maintain a steady level of nicotine in the body a person keeps smoking cigarettes throughout the day increasing the addiction.

As well as these effects, nicotine keeps bad company. For those who smoke, a mixture of chemicals enters the body in addition to nicotine and these cause serious damage to the body. Cigarette smoke includes tar and 4,000 other chemicals, including 43 substances that cause cancer. Others include gases, such as carbon monoxide. Carbon monoxide interferes with the blood's ability to carry oxygen to the body's tissues. (See Poster)

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Tobacco plant

Chewing tobacco

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Common Names

  • Tobacco
  • Cigarettes
  • Cigars
  • Fags
  • Pipes
  • Chewing tobacco
  • Tobacco gum
  • Nicotine patches

Short Term Effects

Nicotine at first causes a rapid release of adrenaline resulting in:

  • Rapid heartbeat
  • Increased blood pressure
  • Rapid, shallow breathing

Nicotine Poisoning (when eaten by children or pets or when young and new to smoking)

  • Tremors
  • Auditory and Visual Hallucinations
  • Headaches
  • Excitement
  • Vomiting and Diarrhea
  • Stomach pains
  • Difficulty breathing
  • Twitching leading to seizures
  • Racing heart rate
  • High blood pressure

Nicotine can cause the cells to release some glucose stores into the blood while at the same time blocking the release of the hormone insulin. Insulin tells the cells to take up excess glucose from the blood. This means that the person has an excess of sugar in the blood.

Some people think that nicotine also curbs the appetite so that not as much food is eaten, while also increasing the basal metabolic rate slightly which means that the body burns more calories while resting. This causes weight loss but doesn't give the health benefits that losing weight by exercising does.

Withdrawal symptoms from nicotine may include tiredness, nervousness, irritability, anxiety, depression, and intense cravings for nicotine. In addition, a smoker may experience an inability to focus and a loss of attentiveness when completing daily tasks. Some say that a better understanding of nicotine's effects may explain why those who find it hardest to stop smoking often have other ailments such as depression or schizophrenia.

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Long Term Effects

Nicotine can increase the level of the "bad" cholesterol, (LDL) that damages the arteries. This leads to heart disease making it more likely to suffer from a heart attack or a stroke.

Circulatory disorders - Nicotine constricts the small arteries reducing blood flow to the limbs and can result in slow healing, gangrene and amputation.

Decreases the ability of stomach ulcers to heal.

Tooth loss and discolouration and inflammation of soft lining of the mouth. (Chewing tobacco)

Some studies show that nicotine may be useful in the treatment of diseases such as Alzheimer's Disease and Tourette's Syndrome due to its effects on the chemicals in the brain. But, for the average person, the health problems associated with using nicotine-containing products are far worse than any benefits.

The biggest problem with nicotine is how easily you become dependent on smoking or chewing tobacco.

  • Psychological - People who are addicted to something will use it compulsively, without thinking of its negative effects on their health or their life. A good example would be someone who continues to smoke, even though they have already lost limbs by amputation due to gangrene.
  • Physiological - Anything that turns on the reward pathway in the brain is addictive. Because stimulating this neural circuitry creates such a good feeling, a person will continue to do it again and again to get those feelings back. Because this effect is lessened with use, more and more of the drug is required to give the same effect so a person goes from one cigarette to a pack of cigarettes or to another drug such as marijuana or heroin. For many smokers, even a day without nicotine is excruciating. Every year, millions of people try to break the nicotine habit; only 10 percent of them succeed. The key is not to start!

The tar and other chemicals which come with the use of tobacco products carry many long term chronic health risks. These include:

  • Smoking deletes viamin C levels and smokers have less effective immune systems than non-smokers.

  • Smoking contributes to the advancement of respiratory diseases such as bronchitis, asthma and emphysema.

  • Smokers are three times more likely to die at an early age from a heart attack or stroke.

  • Cigarette smoking prematurely ages the skin of the face.

  • Women who smoke have smaller babies, more premature births, miscarriages and stillbirths. There is evidence of impairment in the mental and physical development of the children.

  • There is evidence of an early onset of menopause in women smokers.

  • Developing lung cancer and other cancers of throat, larynx and mouth are greatly increased in smokers.

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Scott T & Grice T: The Great Brain Robbery - Allen & Unwin 1997; page 94-95








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Last updated: Tuesday, 28 January, 2014