Smoking or Addiction to Nicotine-one of the most heavily-use addictive drugs in the world
Cigarette smoking has been the most popular method of taking nicotine since the beginning of the 20th century. Research shows that nicotine is highly addictive because it provides an almost immediate kick that causes a discharge of epinephrine from the adrenal cortex. This stimulates the central nervous system and other endocrine glands, which causes a sudden release of glucose.
Stimulation is then followed by depression and fatigue, leading the abuser to seek more nicotine. Addiction to nicotine is one of the most difficult addictions to overcome. Heavy users of heroin and cocaine say it is easier to give up drugs than smoking. Nicotine produces a mild euphoria in many users and increases alertness and concentration.
Studies show a small but measurable improvement in memory and attention when tobacco is inhaled. Some smokers claim that cigarettes have a relaxing effect and reduce stress. Some says nicotine helps release the neuro-transmitter dopamine, similar to the mechanism at work in the euphoria-producing chemistry of opiates, amphetamines and cocaine. However studies also show strong link between depression and smoking.