A toxic alkaloid having the formula C₁₀H₁₄N₂ occurring in both raw and cured tobacco, from which it can be extracted by distillation. Nicotine and related heterocyclic compounds comprise from 5 to 7% of the solids in cigarette smoke. Oxidation of nicotine yields the vitamin nicotinic acid (niacin).  

A toxic alkaloid having the formula C₁₀H₁₄N₂ occurring in both raw and cured tobacco, from which it can be extracted by distillation. Nicotine and related heterocyclic compounds comprise from 5 to 7% of the solids in cigarette smoke. Oxidation of nicotine yields the vitamin nicotinic acid (niacin).  

Nicotine has few uses other than as an insecticidal dust or spray in the form of compounds, e.g., nicotine sulfate. Nicotine solutions are used as fumigants. Inhalation of fumes should be avoided.  

Nicotine has few uses other than as an insecticidal dust or spray in the form of compounds, e.g., nicotine sulfate. Nicotine solutions are used as fumigants. Inhalation of fumes should be avoided.