Objective: To examine nicotine use and its correlates among psychotic patients.

Method: Longitudinal naturalistic study of 176 patients, diagnosed with schizophrenia or schizophrenia-related psychotic disorders, and treated with risperidone at study entry. Levels of nicotine use (smoking, snuffing) were measured along with other relevant ratings and measurements (symptoms, drug treatment, side effects, weight, cognitive functions and outcome) at baseline and once yearly for 5 years.

Results: Nicotine use was twice as common as in the general population. Only few nicotine users had started after onset of psychoses. We could not find any differences among nicotine users and non-users in diagnosis, symptoms, side effects, weight, cognitive functions, personality and outcome, cross-sectionally and longitudinally, ruling against the 'self-medication' hypothesis.

Conclusion: A parsimonious interpretation of the findings is that patients suffering from psychosis fail to desist from nicotine rather than experience significant positive effects of the usage.