Nicotine, a major ingredient in tobacco, rapidly absorbs into the bloodstream whether a tobacco product is smoked, inhaled or chewed. Nicotine affects users of cigarettes, cigars, pipes and chewing tobacco. The drug eventually affects every part of the central nervous system, also called CNS. The system consists of the brain and spinal cord to control and coordinate most functions of the body and mind.
Stimulation
Nicotine, a stimulant, takes several seconds to reach the brain and increases brain activity, the Netdoctor website notes. Nicotine plays a strong role in boosting the pleasure center of the brain. It helps the adrenal glands to release the hormone epinephrine, also known as adrenaline. Nicotine actually stimulates and increases concentration. Many smokers point out it helps them to relax. Shortly after smoking, nicotine users have faster respiration, an increase in blood pressure and heart rate and constriction of arteries. Nicotine suppresses insulin output from the pancreas while more glucose is released into the blood. This increases blood sugar levels in smokers.
Dependency
Many tobacco users become addicted to nicotine because the drug increases levels of the neurotransmitter dopamine, according to the National Institute on Drug Abuse. Dopamine affects brain signals that control reward and pleasure activities. Users of tobacco products may start out slowly but tend to increase their nicotine intake as the body and brain start to adapt to the drug. As smokers smoke more, the body demands more nicotine to receive the pleasurable effects from the stimulant. Users of nicotine need a certain level of the drug to function normally throughout the day. The longer tobacco users go without a regular dose of nicotine, the more uncomfortable they feel until they get the next dose.
Withdrawal Symptoms
The hold nicotine has on users becomes apparent when they attempt to stop using the drug. The unpleasant effects from withdrawal cause many nicotine addicts to go back to using tobacco products. Nicotine can be as addictive as cocaine or heroin, the National Institute on Drug Abuse points out. Withdrawal symptoms include cravings, anxiety, depression, anger, headaches and fatigue. Difficulty concentrating, sleeping disorders and increased appetite also occur. It can take from a few days to a few weeks for the symptoms to disappear. Many long-term users of nicotine need strong support, counseling or medical assistance, such as nicotine replacement therapy, to overcome the withdrawal effects. Withdrawal from nicotine also includes overcoming the emotional attachment. Nicotine users become used to having their dosage at particular times or during certain situations, such as stressful periods.
