[Periods and milestones in the history of dermatology].

The history of dermatology may be divided in five periods. The first period, dominated by the humoral doctrine (humoral pathology), extends through the Antiquity, the Middle Ages, the 1600th, 1700th and the major part of the 1800th century. The second period (1775-1840) is characterized by the development of the "dermatological systems" and the third period (1840-1890) by the advances in pathology and microbiology. During the fourth period (1890-1940) dermatology develops into a discipline of medical science. A fifth period started in the middle of the 1940th when the chemotherapeutic and antibiotic drugs and later the glukocorticoids revolutionized dermatological therapy. From this time the advances in especially immunology, genetics, ultrastructural research and molecular biology have also given us a quite new understanding of the pathogenesis of skin diseases.