[Aggressive and violent behaviour. Diagnosis, prevention, and treatment].

Some mental disorders are associated with an increased illness-related risk of aggressive behaviour. Epidemiologically, substance abuse disorders are most frequently implicated, followed by psychotic disorders. Dealing with the problems of violence and coercion is the oldest problem of psychiatric institutions. Aggressive patient behaviour still represents a typical risk for staff in psychiatric institutions. Associations with patient characteristics such as diagnosis, gender, and age have not been consistently confirmed. Preventive aspects comprise interventions such as adapting institutional processes to patients' needs, patients participating in decisions, and systematic training for staff. Emergency medication and preventive pharmacotherapy are also important. As last resort coercive measures such as involuntary medication, seclusion, or mechanical restraint can be applied. The state of the art in these areas is presented. Ethical considerations and questions of adequateness have a significant effect.