(born March 14, 1854, Strehlen, Silesia, Prussia—died Aug. 20, 1915, Bad Homburg vor der Höhe, Ger.) German medical scientist. After early work on distribution of foreign substances in the body and on cell nutrition, he found uses for staining agents in diagnosis (including that of tuberculosis) and treatment. He also researched typhoid, fever medications, and eye diseases. In one paper, he showed that different tissues' oxygen consumption reflected the intensity of their cell processes. Ehrlich developed a method of stimulating production of antitoxins by injecting increasing amounts of toxin into animals; his work was crucial to the creation of a diphtheria antitoxin. He and Élie Metchnikoff received the 1908 Nobel Prize for Physiology or Medicine. With Sahachiro Hata, he developed Salvarsan, the first effective syphilis treatment, in 1910.
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