Nicotine is an organic compound and is clear to pale yellow in pure form. It is naturally found in tobacco, tomato, and other plants in the Nightshade family. Nicotine is a relatively small molecule and easily enters human body. As nicotine enters the body, it is distributed quickly through the bloodstream and cross the blood-brain barrier. In the brain, nicotine acts on nicotinic receptors and results in releasing a number of neurotransmitters, including acetylcholine, dopamine, endorphins, enkephalins, epinephrine, norepinephrine, and serotonin etc. The increased levels of the neurotransmitters are responsible for euphoria and relaxation.
Nicotine is a highly addictive substance. The addiction has to do with biochemical reactions in the human body. Its addictive nature has been found to show that nicotine activates reward pathways – the circuitry within the brain that regulates feelings of pleasure and euphoria. As mentioned, after nicotine enter human body, a number of neurotransmitters were released. Dopamine is one of the key neurotransmitters actively involved in the brain. By increasing the levels of dopamine within the reward circuits in the brain, nicotine acts as a chemical with intense addictive effects. These effects spur the continued use of tobacco and lead to dependence. Getting dopamine boost is part of the addiction process. Nicotine dependence means you can’t stop using the substance, even though it’s causing you harm. In some people, using any amount of tobacco can quickly lead to nicotine dependence. Nicotine dependence brings a host of health problems. At the same time, quitting tobacco use causes withdrawal symptoms, including irritability and anxiety. Withdrawal from nicotine is both physical and mental. Physically, the body is reacting to the absence of nicotine. Mentally, the user is faced with giving up a habit, which calls for a major change in behavior. Both the physical and mental factors must be dealt with to quit and stay quit.
Many factors contribute nicotine dependence. The genes we inherit play a role in some aspects of nicotine dependence. The likelihood that we will start smoking and keep smoking may be partly inherited. Some people experiment with smoking and don’t experience pleasure, so they never become smokers. Other people develop dependence very quickly. Some “social smokers” can smoke just once in a while, and yet another group of smokers can stop smoking with no withdrawal symptoms. These differences may be explained by genetic factors that influence how nicotine receptors on the surface of our brain’s nerve cells respond to nicotine. People who have mental illness, such as, depression, schizophrenia, substance abuse etc, are more likely to be smokers. Smoking may be a form of self-medication for these disorders.
It is important to remember that even though you quit smoking, nicotine craving remains with you for the rest of your life. Never test this hard way and stay absence of tobacco smoking!