For anyone that has smoked, they understand just how addictive and dependant that a person can become on the cigarette. However, for those that have never smoked, they do not even begin to understand the mood swings that are going on inside of the smoker. They simply view this person as grumpy and irritable. And in fact, they are definitely irritable and grumpy, yet they themselves are feeling nervous, and have that anxious feeling just because they want to smoke so badly. This is what makes it so hard for people to stop smoking once they are addicted.
Those that smoke are going to find that upon that first puff of a cigarette that they are going to have this immediate feel good feeling that goes through their body. This is the effect of the nicotine on the body. And this feeling is what makes the body start to crave nicotine and then finally become dependent upon it in order to feel good. It is the classic example of doing something and then being rewarded for it. The cigarette is what the person does, while the feeling that this gives them is the reward for it. Most people cannot understand this feeling. And in order to understand the mood swings, the person must understand the feeling that the smoking of a cigarette gives the person.
Many people compare the feel good of nicotine to that of an anti depressant. They feel good for the moment, like every care in the world is gone, hence the reason that so many people smoke when they are stressed. But, unlike an anti depressant that feeling only lasts a few minutes after they smoke the cigarette. Which then encourages the body to want another cigarette to get this feeling back. And if the person waits too long in between these cigarettes, the person actually becomes very depressed. Which is one of the leading moods that the cigarette can put people into.
For those that try to quit smoking, then the mood swings intensify to the highest degree. Which is why so many people are unable to quit. The person is irrational in most cases, they may find that things that never bothered them before, really start to annoy them to the point that they scream and go into a fit of rage. For example, hearing someone clicking their pen, may have never bothered the person before, but all of a sudden they have the extreme urge to break the pen to stop the clicking. Which is not appropriate behavior at all, but this just gives non smokers a glimpse into the mood swings that people are feeling upon quitting smoking and what they may experience once they start going through slowing down how much they smoke.
With the help of many drugs out there, the person can help to minimize the mood swings that they are experiencing. However, they are going to find that they still may feel some of these from time to time as the brain tries to go back to the way that it was before the person began smoking. It is a long and complicated process that is full of ups and downs.