The medicinal leech in Jewish writings

Leeches were widely used for healing throughout antiquity and the Middle Ages. The rabbinic responsa literature acknowledges the use of leeching for the prevention and treatment of certain illnesses, and classic Jewish sources including the Bible, Talmud, and Codes of Jewish Law describe leeches and mention their medicinal use. Although the swallowing of a leech is considered dangerous and may lead to abdominal swelling, the Talmud describes an oral concoction containing leeches in wine for patients with enlarged spleens. It is also documented that engorged leeches placed in salt quickly discharge their blood and can be used again. Modern plastic and microsurgery have rediscovered the medicinal leech, Hirudo medicinalis, to reduce venous congestion. Clearly, the value of this annelid worm lies in its secretion of an anticoagulant known as hirudin, which has several advantages over heparin. One cannot help but marvel at the wisdom and ingenuity of our forefathers.