Malaria fever therapy for general paralysis of the insane in Denmark.

This article explores the history of general paralysis and malaria fever therapy in Denmark. I argue that the small size of the country gave Danish psychiatrists excellent opportunities for performing statistical studies of general paralysis in the 19th century. In the early 1920s malaria fever therapy was introduced in Danish mental hospitals and raised hopes of a cure for paralytics. Malaria fever therapy became popular among Danish psychiatrists, but the new therapy also raised ethical questions and led to the first regulations concerning informed consent in the history of Danish psychiatry.