He was well- versed in the ancient Greek language and he was an admirer and critic of Galen. Rhazes was among the outstanding physicians and medical scholars in his time and made notable contributions in the fields of theoretical and practical medicine.
A musician during his youth he became an alchemist. He discovered alcohol and sulfuric acid. He classified substances as plants, organic, and inorganic. At age 30, he undertook the study of medicine. His teacher in medicine was Ali Ibn Sahl Rabban al-Tabari, a physician and philosopher born to a Jewish family in Merv, Tabaristan.
As a genuine chemist and physicist, he performed a great deal of research and laid the foundation for scientific chemistry to replace alchemy, having written several books and treatise in the field. He discovered and purified alcohol (ethanol) and pioneered its use in medicine.
Major contributions of Rhazes to medicine were:
*The book Kitab al-Mansuri (Liber Al Mansuri), which was dedicated to the Samanid ruler of Ray
*Kitab alHawi (Liber Continens, meaning a comprehensive book or encyclopedia)
*Kitab al -Judari wa al-Hasabah, the first scientific description of a smallpox and measles as distinct disease in late ninth and early tenth century.
Rhazes was the first to utilize neuroanatomy in the localization of lesions of the nervous system and to correlate them with clinical signs. He described nerves as having motor and sensory functions while enumerating seven cranial nerves from the optic to the hypoglossal nerves and 31 spinal nerves.
His explanation of why survivors of smallpox do not develop the disease a second time is the first theory of acquired immunity.
He was one of the first to appreciate the influence of diet on the function of the body and predisposition to disease. Neurologically, Rhazes described sciatic nerve disease, facial nerve paralysis, neurotrauma, tremors, epilepsy, headaches, and hemiplegia. Rhazes was the first to clearly recognize a concussion.
Rhazes was among the two greatest physicians in medieval Iran. Rhazes was followed by Avicenna (937–1037) and was regarded by him as an honorable and distinguished scholar. Rhazes followed Hippocrates and Galen in his works, but Rhazes combined textual medicine with his clinical observations.
Abubakr Muhammad Ibn Zakaria Razi (865 – 925): Physician, chemist and philosopher
