Leeches Are Beneficial
Did you know leech comes from the word laece, meaning "physician"? Medicinal leeches (e.g., Hirudo verbena, Hirudo medicinalis) have been used in medical practice since the 19th century, and medicinal leech therapy (MLT) is centuries old.
In 2004, the U.S. Food and Drug Administration approved and began regulating these bloodsucking aquatic animals as medical devices to be used only under the direction of medical professionals in hospital settings.
Leeches are primarily beneficial in the removal of locally congested blood in delicate areas. Leech saliva contains substances that anesthetize the wound, dilate the blood vessels to increase blood flow, and prevent the blood from clotting. The resulting wound is painless and will bleed for an average of 10 hours, mimicking venous circulation, relieving congestion, and allowing the restoration of normal blood flow.
Leeches are especially useful in plastic surgery to minimize scarring and in grafting procedures where the prolonged bleeding induced by a leech’s bite allows the graft to reestablish its own circulation.
For additional details, download A Guide to Applying, Maintaining, and Storing Medicinal Leeches.