| As nicotine enters
the body, it is distributed quickly through the bloodstream and
can cross the blood-brain barrier. On average it takes about
seven seconds for the substance to reach the brain when inhaled.
The half life of nicotine in the body is around two hours. The
amount of nicotine inhaled with tobacco smoke is a fraction of
the amount contained in the tobacco leaves. The amount of
nicotine absorbed by the body from smoking depends on many
factors, including the type of tobacco, whether the smoke is
inhaled, and whether a filter is used.
For chewing tobacco, dipping tobacco and snuff, which are held
in the mouth between the lip and gum, or taken in the nose, the
amount released into the body tends to be much greater than
smoked tobacco. Nicotine is metabolized in the liver by
cytochrome P450 enzymes (mostly CYP2A6, and also by CYP2B6). A
major metabolite is cotinine.
Pharmacology
Pharmacodynamics >>
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Nicotine
History and name
Chemistry
Pharmacology
1.Pharmacokinetics
2.Pharmacodynamics
2.1 In adrenal medulla
2.2 In CNS
Psychoactive effects
Dependence
Toxicology
Therapeutic uses
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