History of malaria and brain which are the most constant post-mortem indications of chronic malaria infection. He related the prevalence of malaria in swampy areas to the presence of flies and recommended swamp drainage to prevent it. In the nineteenth century, the first drugs were developed to treat malaria and parasites were first identified as its source. French chemist Pierre Joseph Pelletier and French pharmacist Joseph Bienaimé Caventou separated in 1820 the alkaloids cinchonine and quinine from powdered fever tree bark, allowing for the creation of standardized doses of the active ingredients. Prior to 1820, the bark was simply dried, ground to a
Tonic (physiology) Tonic (physiology) Tonic in physiology refers to a physiological response which is slow and may be graded. This term is typically used in opposition to a fast response. For instance, tonic muscles are contrasted by the more typical and much faster twitch muscles, while tonic sensory nerve endings are contrasted to the much faster phasic sensory nerve endings. Tonic muscles are much slower than twitch fibers in terms of time from stimulus to full activation, time to full relaxation upon cessation of stimuli, and maximal shortening velocity. These muscles are rarely found in mammals (only in the muscles moving the