a very poisonous alkaloid that in its pure state is a colorless, pungent, oily liquid, having an acrid burning taste. It is a constituent of
tobacco, and is also produced synthetically. It is administered orally, intranasally, or by inhalation as an aid to smoking cessation. In water solution, it is sometimes used as an insecticide and plant spray.
Although nicotine is highly toxic, the amount inhaled while smoking tobacco is too small to cause death. The nicotine in tobacco can, however, cause indigestion and increase in blood pressure, and dull the appetite. It also acts as a vasoconstrictor. Researchers link
smoking with heart disease, lung cancer, and other diseases.
nicotine poisoning poisoning by
nicotine, such as in children who eat cigarettes, workers who handle wet
tobacco leaves, or persons who overuse nicotine gums or patches. Symptoms include stimulation followed by depression of the central and autonomic nervous systems and occasionally death due to respiratory paralysis. Called also
nicotinism.