Nicotine

An alkaloid which is the active principle of tobacco C10H14N2 It occurs in tobacco plants Nicotiana tabacum and Nicotiana rusticum to the extent of 2 to 8 in combination with malic acid or citric acid It is a colorless transparent oily liquid having an acrid odor and an acrid burning taste It is intensely poisonous The apparently addictive effects of tobacco smoking have been ascribed largely to the effect of nicotine and the controlled administration of nicotine on various forms has been used as a technique for assisting efforts to stop the smoking habit