Johann Jakob Wepfer

Johann Jakob Wepfer (December 23 1620 - January 26 1695) was a Swiss pathologist and pharmacologist who was a native of Schaffhausen. He studied medicine in Strasbourg, Basel and Padua, and in 1647 returned to Schaffhausen to practice medicine.

Wepfer is remembered for his pioneer work concerning vascular anatomy of the brain, and the study of cerebrovascular disease. He was the first physician to hypothesize that the effects of a stroke were caused by bleeding in the brain. He also mentioned that these symptoms could be caused by a blockage of one of the main arteries that supply blood to the brain. From his postmortem studies, he provided information concerning the carotid and vertebral arteries that supply the brain with blood. in 1658 he published a classic treatise regarding strokes, titled Apoplexie.

Wepfer also made important contributions in the fields of experimental pharmacology and toxicology. He performed pioneer research concerning the effects of toxic substances on the heart and blood's circulatory system. He performed important experiments concerning the toxicity of water hemlock, arsenic, monkshood, et al. His most important written work in this field was the 1679 Historia cicutae aquaticae.