18 patients with acute clozapine poisoning, 6 female and 12 male, were analyzed. The mean age was 42.8 years. Six patients were intoxicated only clozapine. Mixed poisoning (clozapine and other factor) was diagnosed in nine cases. Among the additional factors dominated psychotropic drugs. According to the Poisoning Severity Score (PSS) criteria in the study group was only a one mild intoxication. Acute pneumonia developed in 3 patients, acute bronchitis and rabdomyolysis were reported in one case. The most common symptoms included: agitation, confusion (83.3%), tachycardia (77.8%), CNS depression (66.7%), excessive mucus production in bronchi, hypersalivation (44.4%), miosis (50%). Disordered breathing requiring intubation or mechanical ventilation occurred in 27.7% of poisoned. The average duration of hospitalization was less than 7 days.