The medicinal use of leeches (Hirudo medicinalis L.)

The medicinal use of leeches (Hirudo medicinalis L.) dates back to ancient Egyptians around 1300 BC; the Greek physician Galen (130 to 201 AD) commonly used leeches for bloodletting. The 19th century heralded the widespread use of leeches for bloodletting—leading to a leech shortage from 1825 to 1850 in France requiring the importation of leeches from America. By the end of the 19th century, the medicinal use of leeches had lost popularity due to adoption of the modern concepts of pathology and microbiology.

Recombinant hirudin has been used successfully in the treatment of Kasabach-Merritt syndrome, a condition leading to loss of circulating platelets and fibrinogen. Paradoxically, low-dose subcutaneous hirudin normalized fibrinogen and platelet activity. 11

In a randomized trial, the use of leeches significantly reduced knee pain in adults with knee osteoarthritis compared with topical diclofenac. 23

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