Background: There is repeated evidence, that psychotic condition is of ten triggered by the usage of methaphetamines, in the contrast to the consumption of the opiates. Despite of this fact, not every patient with methamphetamine dependence is suffering from psychotic symptoms. The aim of the study was to find out about the prevalence and time sequence of development and treatment of combined mental disorder: methamphetamine dependence and psychotic disorder. Methods: We have conducted retrospective search of the medical records for the occurrence of the psychotic conditions among the all patients treated with diagnosis of methamphetamine dependence in the Centre for Treatment of Drug Dependencies in Bratislava in the time period from 2004 to 2008. Results: 29 % of 318 patients had diagnosis of psychotic disorder. It was more frequent among injecting drug users. Two main kinds of psychotic disorder with respect to the etiopathology were detected: 1) toxic psychosis caused by the usage of psychoactive substance, methamphetamines; 2) psychotic disorders with schizophrenic signs and symptoms of affective disorders, during the abstinence, which is lasting over the period of 6 months. Conclusions: Toxicological screening with respect to the high prevalence of psychotic signs is part of good clinical practice in the process of making diagnosis of acute psychotic conditions in the emergency psychiatry. The problem of diagnosis according to ICD-10 WHO criteria is remaining after the exclusion of typical toxic psychosis. Combined diagnosis, of e.g.: schizophrenic disorder and dependence from methamphetamines, seems to be the most relevant, also from the pharmacotherapeutical point of view, if the psychotic symptomatology is lasting over six months.

Key words: methamphetamine dependence – psychosis – combined diagnosis