Branch of medicine concerned with mental disorders.
Until the 18th century, mental health problems were considered forms of demonic possession; gradually they came to be seen as illnesses requiring treatment. In the 19th century, research into and classification and treatment of mental illnesses advanced. psychology in the mid-20th century. Psychiatrists hold medical degrees and can prescribe drugs and other medical treatments in addition to conducting psychotherapy. The psychiatrist often works as a member of a mental health team that includes clinical psychologists and social workers.