A slippery, black creature with three jaws and 100 teeth feasting on your blood. Sounds medieval, does it not?
Yet in this age of high-tech modern medicine, leech therapy is alive and well.
When it bites into the skin, the medicinal leech injects anesthetics to avoid disturbing its meal, chemicals that dilate the blood vessels to get a better flow, and anticoagulants to stop the blood from clotting. This is all before it starts to suck out its meal — a leech can take in up to 10 times its own body weight in human blood.
You may have heard of the practice of bloodletting, an ancient system of medicine in which “tainted” blood was extracted from a patient in the hopes the disease or infection would be removed with it. The therapeutic use of leeches is recorded in ancient Egyptian and Greek handbooks of medicine.
In the centuries that followed, patients were bled for a wide variety of supposed bodily imbalances, from hemorrhoids to headaches and even depression. In 19th-century Europe, Hirudo medicinalis, the medicinal leech (leech therapy is also known as hirudotherapy), was so popular that it was harvested to near-extinction.
By the 20th century, once medicine abandoned the concept that most diseases were caused by an excess of blood, leech therapy fell out of favor and was consigned to the history of unscientific medicine.
Then, in 1985, a dog bit off the right ear of a 5-year-old boy from the Boston suburbs. The boy’s physician, a plastic surgeon named Joseph Upton, reattached the ear, but it began to turn black and die because blood could get into it but not out again due to clotting in the veins.
Blood-thinning agents didn’t help, nor did lancing the ear. Luckily, however, Upton remembered an article he had once read about the therapeutic effects of leeches on congested tissue.
He had 30 leeches flown from a company in Wales to Boston and attached two to the boy’s ear. In minutes it began to recover its healthy color, and after a couple of days the organ was fine, and Upton became the first doctor to have successfully reattached the ear of a child using leeches.
Leeches were approved in 2004 by the FDA as a “medical device,” enabling new leech-farming companies from other countries to enter the market and for surgeons to use to drain pooled blood after surgery.
The most common use is after a digit replant (when a severed digit is surgically reattached) and reconstructive flap surgery, similar to a skin graft. Medical practitioners have also used leeches to treat varicose veins, neuropathy and blocked arteries as well as for reduction of pain from osteoarthritis.
For the time being, leech therapy only seems to be available in major urban areas — Boston and New York City among them. The ones that do offer it aren’t exactly advertising it, either. It’s not surprising it would take such a treatment to catch on and be part of the healthcare mainstream.
The anti-inflammatory and other compounds in leech saliva are still not fully understood, and there remains no consensus among the medical community regarding how long leeches should be applied or how many to use at once.
Therapy is painless, anyway. The leech secretions that ensure it can feed uninterrupted also mean the patient doesn’t feel the bite — because let’s face it, the idea of having leeches placed anywhere on your body can seem a little freaky. The treatment is also the leech’s last meal — each leech is dunked in alcohol so it dies and it is disposed of.
While leech therapy isn’t covered by health insurance, it is a cost-effective treatment, relatively speaking, to more traditional therapy. The use of leeches has fewer side effects than the standard treatment of nonsteroidal anti-inflammatory drugs, and they are more effective in relieving pain and stiffness than the best topically applied medication.
There are, of course, some risks to using leeches. Since leeches rely on a colony of bacteria in their gut to digest blood, it is possible for people treated with leeches to get a bacterial infection. You can’t sterilize leeches like you can a scalpel.
Risk of infection is one of the reasons why it’s common practice for caregivers to give leech therapy patients antibiotics as a preventative measure.
As with any other medical treatment, there are pros and cons to leech therapy. But there’s no looking past the advantages of medicine that comes straight from Mother Nature.