Objective. To study the characteristics of prolactin secretion in patients with a first psychotic episode (FPE) with regard to disease severity, gender and patient’s neuromediator system state. Material and methods. Author studied 76 patients with schizophrenic spectrum disorders and 34 normals (control group). Results and conclusion. There was a significant negative sex-related correlation between the severity of psychopathologic symptoms and plasma prolactin levels. Based on the results, author attempted to explain the hormonal disbalance in the patients with FPE taking into account the state of monoaminergic mediator systems in patients.