[Psychiatric and psychological features of nicotine dependence].

Nicotine dependence involves both psychological and physiological dependence on nicotine. Evidences suggest that nicotine depends on dopamine for its reinforcing effects. A recent summary description of the clinical aspects of nicotine dependence disorders is provided in the DSM-IV-TR of the American Psychiatric Association. Nicotine withdrawal is defined by the DSM-IV-TR as a condition in which a person, after using nicotine daily for at least several weeks, exhibits at least four of the following symptoms within 24 hours after reduction or cessation of nicotine use: (1) dysphoric or depressed mood, (2) insomnia, (3) irritability, frustration or anger, (4) anxiety, (5) difficulty concentrating, (6) restlessness, (7) decreased heart rate, (8) increased appetite or weight gain. Among those symptoms, depression needs special consideration.