Leech drug. Hand covered with medicinal leeches, Hirudo medicinalis, as it holds a vial of a drug, orgelase, which is derived from them. Orgelase is a type of hyaluronidase enzyme which widens blood vessels so that the flow of fluid is increased. It can be used in an injection to quicken the dispersal of another drug. It might also be used to treat conditions caused by restricted flow in blood vessels, such as inflammation, migraine and heart disease. The drug is found in the saliva of blood-sucking leeches and can be harmlessly extracted (milked") from them."