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NICOTINE ADDICTION
If you have tried to quit smoking, you know how hard it can be. It is hard because nicotine is a very addictive drug. For some people, it can be as addictive as heroin or cocaine.
Quitting is hard. Usually people make two or three tries, even more, before finally being able t
2、o quit. Each time you try to quit, you can learn about what helps and what hurts.
Quitting takes hard work and a lot of effort, but you can quit smoking.
RECOGNIZING YOUR ADDICTION
Every smoker is addicted to a slightly different combination of “stimulants” in cigarettes and the act of smoking.
3、A stimulant is the addictive property in a cigarette that keeps you craving for more, even though you know you shouldn’t.
You must find out what you like about smoking. Write that reason down. By writing it down, you will understand it.
WHY DO YOU SMOKE?
Is smoking a “positive” experience for yo
4、u? If so, then you have conditioned your mind and body, through prolonged exposure to smoking, to get positive feelings when you smoke.
Non-smokers don't experience the roller-coaster ride of the highs and lows. Instead, they maintain a much higher level of well-being. They don't need a cigarette t
5、o relax – they have learned to relax naturally.
The Effects of Nicotine
Nicotine affects almost every system in the body. When you take a puff, your heart beats faster, your pulse quickens, your veins constrict, your blood pressure increases. Your adrenal glands pump out adrenaline that increases
6、 your heart rate, relaxes many of your smooth muscles, and raises your metabolic rate.? Even the electrical activity in your brain changes.
These are powerful biological effects. Indeed, nicotine is a very powerful drug. In fact, it is one of the most toxic of all drugs, comparable to cyanide. Take
7、 enough nicotine and it can kill you. But the amount of nicotine in a single cigarette is only 8 to 9 milligrams on average.
The amount of nicotine that smokers inhale from each cigarette is even smaller. Most popular brands of cigarettes deliver less than 1.5 milligrams per cigarette. This amount
8、may be somewhat higher or lower for each smoker, depending on how deeply you puff and how many puffs you take from each cigarette.
But nicotine is so potent that even this small dose causes significant changes in the functioning of numerous organs and systems in your body. When people first take up
9、 smoking, these physiological changes seem extremely unpleasant. Beginning smokers usually experience nausea, dizziness, headache, stomach upset, coughing and other uncomfortable symptoms. But people who continue to smoke soon develop a tolerance to these symptoms, until they become unnoticeable.
T
10、olerance is a term used to describe an important feature of addiction. Tolerance has developed when, after the repeated administration of a drug (in this case, nicotine) produces a decreased effect. As well, tolerance has developed when increasingly larger doses must be administered to obtain the ef
11、fects observed with the original dose.
What does this mean for the smoker? The small dose of nicotine delivered by several puffs on a cigarette may make people feel ill the first few times they try smoking. But after they’ve been smoking for a week or so (repeated “self-administration” of nicotine)
12、, several puffs and even an entire cigarette no longer have that effect. Now they’ll feel ill only if they smoke several cigarettes one after another (a larger dose).
Psychologically, tolerance to the unpleasant effects of nicotine allows the smoker to focus on nicotine’s pleasurable physiological
13、effects. Many smokers don’t realize that nicotine’s effects on the heart, the nervous system, and the endrocine system are significant contributors to the relaxation, alertness, stress relief, and other good feelings they experience.
This combination of physiological and psychological effects provi
14、des so many positive reinforcements that smoking quickly becomes an established habit.
As the term tolerance implies, a smoker actually becomes accustomed to having a certain level of nicotine in his or her body. In fact, research studies have shown that (without realizing it) smokers regulate the
15、number of cigarettes they smoke in order to maintain their own personally preferred level of nicotine. For example, smokers who are given a very high nicotine cigarette will puff less often than usual, so they don’t take in more nicotine than their preferred amount. Likewise, with a low nicotine cig
16、arette, the smoker will take more puffs than usual, in order to get that preferred amount of nicotine.
When no cigarettes are smoked for a while (when someone is trying to quit), the smoker doesn’t get any nicotine. And it is the lack of nicotine that produces unpleasant physiological symptoms in t
17、he body. Medically, these symptoms are called “withdrawal effects.”
To relieve these withdrawal effects, many smokers must continue to take in their usual amount of nicotine. This is a sign of “physical dependence” on nicotine. Doctors define physical dependence as a change in the body’s functionin
18、g that is produced by repeated administration of a drug, such that continued doses of the drug are needed to prevent withdrawal symptoms.
But that’s not all. Smokers also become accustomed to the psychological effects of smoking. After the smoking habit is established, the smoker needs to smoke in
19、to feel “normal.” In other words, the effects produced by nicotine, and the behaviors associated with smoking, become necessary to maintain the person’s optimal state of well-being. This condition is referred to as “psychological dependence.”
At the extreme, many smokers who run out of cigarettes o
20、r are unable to smoke, become totally preoccupied by thoughts of having a cigarette. This behavior is often referred to as “compulsive drug use.”
Is Smoking An Addiction?
Physiological and physical dependence, withdrawal, and compulsive drug use are the defining characteristics of “drug addiction
21、.” Does this mean that smoking is an addiction? Certainly, the smoking habit meets many of the criteria needed to qualify as an addiction, including:
1. A highly controlled or compulsive pattern of drug use. The experienced smoker has a lot of smoking patterns that (if broken) are disturbing.
2.
22、Psychoactive, or mood-altering effects involved in the pattern of drug taking.
3. Drug functioning as a reinforcement to strengthen behavior and lead to further drug ingestion. It’s the nicotine that keeps people smoking.
Using these criteria, the U.S. Surgeon General’s Report (in 1988) on smoki
23、ng made several major conclusions:
· Cigarettes and other forms of tobacco are addicting.
· Nicotine is the drug in tobacco that causes addiction.
· The pharmacological and behavioral processes that determine tobacco addiction are similar to those that determine addiction to drugs such as heroi
24、n and cocaine.
All smokers show signs of physical and psychological dependence on nicotine. Their bodies crave nicotine, and they will smoke until their bodies have taken in a certain level of nicotine. Thus, addiction is more a matter of degree. Its not if you are addicted but how addicted you are.?
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