Introduction. Mental illnesses have been a health prob-lem for many centuries. The forms, characters and classifications of these diseases have been different, just as their image is differ-ent in social consciousness, shaped by worldview systems trying to explain physical, social and spiritual reality. The frequency of mental illnesses and disorders is increasing in Poland, which increases the likelihood of contact with these sick nurses during their professional activities.
The aim of the study. The aim of this work was to present the problems of mental health and a brief description of the most common mental diseases and disorders.
Selection of material. The search was conducted in the Scopus database for the period 2004-2019, using the terms mental health, depression, schizophrenia, bipolar affective disorder, anxiety disorders. From the literature found in the Google Scholar data-base, studies were selected which, in the opinion of the authors, would be most useful in the preparation of this study.
Conclusions. Due to the similarity of somatic symptoms of dis-eases and mental disorders and the symptoms of life-threatening conditions, these symptoms should be interpreted and differenti-ated very carefully. Such a procedure becomes particularly im-portant in the hospital emergency department or in the emergency room.