Nicotine is one of the most addictive substances known to man. This powerful and very fast acting drug is the chemical which causes addiction to cigarettes. Effects of Nicotine: Facts Nicotine affects many different parts of the body at the same time. After just one puff of a cigarette it begins to act on the central nervous system, brain and other parts of the body. It actually stimulates your system, even though it makes you feel relaxed. Nicotine affects chemicals in the brain and, after a puff, you usually feel good for a moment or two, which is why many smokers view smoking as stress relief when under pressure. Some areas of the brain are pleasure related and when stimulated give the feeling of relaxation and reduced anxiety. Efforts to provide treatment using Nicotine Replacement Therapy (NRT) have also lead to incidents of nicotine gum addiction and other nicotine addictions. Nicotine withdrawal Nicotine withdrawal is a term used to describe the effects felt by a person who is nicotine dependent and suddenly stops or significantly reduces his/her nicotine intake. Since smoking cigarettes is the most popular form of nicotine use, the effects of nicotine withdrawal have been most commonly observed in people who are in the process of quitting smoking. Symptoms can include craving cigarettes, becoming irritable, intense headaches and increased blood pressure. Persons who have smoked a higher number of cigarettes or for a longer period of time are more likely to experience these symptoms, although almost all people who try to ‘kick the habit’ suffer some form of withdrawal symptoms from the drug. When regular smokers quit, they often have strong cravings when they are placed in situations associated in their minds with smoking (e.g. leaving home in the morning, on a coffee break, etc). The most common symptoms of nicotine withdrawal are impaired concentration, irritability, tension, disturbed sleep or drowsiness, intense longing for a cigarette/nicotine, headaches, and an increased appetite leading to weight gain. Sometimes people can experience nicotine withdrawal when cutting down to light cigarettes or cutting down the number smoked.