Abu Sahl ‘Isa ibn Yahya al-Masihi al-Jurjani;
(Persian: ابو سهل عيسى بن يحيى مسيحی گرگانی) was a Persian physician, from Gorgan, east of the Caspian Sea, in Iran.
He was the teacher of Avicenna. He wrote an encyclopedic treatise on medicine of one hundred chapters (al-mā’a fi-l-sanā’a al-tabi’iyyah; Arabic: المائة في الصناعة الطبيعية), which is one of the earliest Arabic works of its kind and may have been in some respects the model of Avicenna’s Qanun.
He wrote other treatises on measles, on the plague, on the pulse, etc.
He died in a dust storm in the deserts of Khwarezmia in 999–1000 CE.