The discovery and application of antipsychotics led to a strong boost in the treatment of psychotic disorders. The mechanism of their action also includes the adverse effects of the neurological and non-neurological system that cause dissatisfaction of the patient resulting in refusal of co-operation when taking medication and aggression towards medical staff. Neurological side effects are most prominent in the use of classical antipsychotics such as promazine and haloperidol and include the occurrence of sedation, tremors, extrapyramidal symptoms, of which the most severe is tardive dyskinesia. The most dangerous neurological adverse event for a patient is a malignant neuroleptic syndrome, a life-threatening condition that can occur at any time of treatment when applying any psychopharmaceuticals. Harmful effects on the part of other organic systems appear more frequently in the application of antipsychotics of the newer generation and include metabolic, endocrinological, cardiovascular, gastrointestinal, haematological, dermatological and ocular changes. Role of the nurses in the recognition of harmful effects of antipsychotic therapy includes strategies for monitoring, teaching, co-operation and patient protection. Nurses spend most time with the patient and are able to detect changes in time, monitor the reaction, and intervene adequately. Within the framework of care for mentally ill people with a psychotic disorder, the ability to create a therapeutic relationship with the patient, in order to achieve sense of security and trust, is of great importance. Assessing the intellectual capabilities of each patient individually is important in the application of appropriate activities for alleviating intrapsychic tension. Early recognition of harmful symptoms and proper nursing care that involves individually planned interventions aimed at solving problems and meeting basic needs are a prerequisite for a better and independent functioning of patients, reduction in the feeling of fear and better co-operation in the application of therapeutic procedures.