Nicotine Pharmacology
As the National Institute on Drug Abuse explains, when nicotine gets into the bloodstream, it has a number of effects on the body's physiology. Nicotine stimulates the adrenal glands to produce a chemical called norepinephrine (also known as adrenaline) which causes the heart rate to increase, increases the blood pressure, causes glucose to be released into the blood and also stimulates the central nervous system. One effect of this stimulation is the release of dopamine, a chemical that gives the brain a sensation of pleasure.
Withdrawal and Nicotine Replacement
As an article in the February 2004 issue of the "British Medical Journal" explains, the most common use of nicotine gum is to help patients deal with the withdrawal symptoms associated with stopping the use of tobacco. When tobacco is used on a regular basis, the brain becomes accustomed to the heightened levels of norepinephrine and dopamine in the brain. This causes the brain to alter its chemistry so that it becomes accustomed to the chemical changes that nicotine provides. When you try to quit smoking, the altered brain chemistry perceives a lack of norepinephrine and dopamine, leading to withdrawal symptoms (which also create a craving for nicotine). The purpose behind nicotine gum is to provide a non-tobacco source of nicotine so as to replace the nicotine in the bloodstream. This reduces withdrawal symptoms and curbs tobacco cravings.
Nicotine Absorption
According to the MedLine website, when nicotine gum is chewed, it releases small amounts of nicotine. The nicotine gets absorbed by the tissues in the mouth and then travels into the bloodstream. Nicotine gum is most effective when the gum is chewed slowly until the chewer feels a tingling sensation in his mouth. The gum should then be held in between the tongue and the cheek (for maximum nicotine absorption) until the tingling sensation is gone. The process can then be repeated until the nicotine in the gum is depleted.
