Nicotine dependence: a preventable risk factor for other diseases.
 Nicotine meets all critical criteria for an addictive drug.
 Furthermore, there is no evidence that there would be widespread compulsive use of tobacco without nicotine.
 These findings have led to consideration of the cigarette as a contaminated vehicle for an addictive drug (nicotine).
 Nevertheless, nicotine itself may also be used therapeutically to reduce exposure to carcinogens and other tobacco toxins.
 Nicotine replacement is a useful adjunct in treating tobacco dependence.
 For example, nicotine replacement in the form of a polacrilex resin (chewing gum) can alleviate physically based signs and symptoms of tobacco abstinence.
 The fact that this form of nicotine replacement is not attractive to non-users of tobacco has opened the door to the use of nicotine in a therapeutic modality, permitting hope of eliminating tobacco dependence.
