Leeches were used for hundreds of years in treating patients will all kinds of conditions, from cancer to mental illness. It was an offshoot of bloodletting for curing what ails ya. Today we tend to look at leeches as medical treatment in the same way we see bloodletting- they didn't have anything better back then. But the more we learn about leeches, the more useful they become.
Leeches live by drinking blood, so they've developed some specific chemicals to enable their diet. Leech saliva contains an anticoagulant called hirodine, plus other anti-inflammatory agents, antibiotics, and pain relievers. All these things help a leech stay attached to their host and digest their blood. Using these chemicals straight from a medicinal leech can target a specific area on the patient, such as a finger after it's been severed and reattached, without having to flood the whole body with medicine.
The reintroduction of leeches as a medical treatment has a problem, though, in that medicinal leeches (Hirudo medicinalis) are a threatened species. Read about the usefulness of medicinal leeches and the efforts to breed them for the purpose at the Conversation. -via Geeks Are Sexy
(Image credit: GlebK)
