Leeches Are Bizarrely Good for Human Health

They are rumored to help with painfully long erections and reattach severed limbs.

 Medicinal Leeches and Where to Find Them

The rise, fall, and resurrection of the humble leech.

 Modern medicine still needs leeches

For microsurgeons who reattach fingers, ears, and other extremities, leeches remain an invaluable medical device.

Hirudotherapy (Leech Therapy)

Leeches have been used in medicine for thousands of years. Leeches remove blood (“phlebotomize”) from their host, and they release pain-killing (anesthetic) and blood-thinning (anticoagulant) substances with their saliva.

Some doctors still use leeches. This is what it's like to be treated by one

If you had one of your fingers severed and got it surgically reattached, a doctor might prescribe an unexpected therapy to prevent blood clots: a leech. Leeches, of course, were used in ancient times as part of the pseudoscientific practice of bloodletting. But few people are aware that they've made a comeback in legitimate medicine over the past few decades, and are now used in rare cases as a way to maintain blood flow in surgically reattached tissue.

At Natural History Museum, the Lowdown on Leeches

As far as I'm concerned, few organisms, invertebrate or otherwise, can compete with the leech when it comes to the "ick" factor. I wouldn't say it rises to a phobia with me. But, all things considered, I probably prefer predators that are willing to bite you—from snakes to lions to even some people—to bloodsuckers.

Bloody Suckers

The ancient physician’s art of using leeches has made a modern medical comeback: the worms help doctors do everything from reattach severed fingers to treat potentially fatal circulation disorders.

Curious Kids: why do leeches suck our blood?

The one area of medicine where leeches are still helpful is using them to improve blood circulation in the skin. They also reduce the chances of blood clotting when that could be dangerous in some sick people. However, these days we can make an artificial version of the chemical leeches use to prevent blood clots, which is called “hirudin”.

Despite the ‘Yuck Factor,’ Leeches Are Big in Russian Medicine

Leeches — yes, leeches — are still widely prescribed in Russian medicine, about 10 million of them every year, in many cases as a low-cost substitute for blood thinners like warfarin.

History of Leech Therapy

Medicinal leeches are as old as the Pyramids. Literally. Records indicate that Egyptians used leech therapy over 3,500 years ago and leeches (often mistakenly credited as cobras) are included in the hieroglyphics painted on the walls.

Leeches Make a Medical Comeback

Modern-day medicinal use of leeches is limited to the treatment of blood-clotting problems after surgery. Doctors from Germany's Kliniken Essen-Mitte maintain that leech saliva contains anti-inflammatory substances and other chemicals which could relieve symptoms of arthritis.

The Stuff That Helps Leeches Get Their Fill of Blood

Researchers examined the arsenal of anticoagulants used by marine leeches to feed on turtles, fish and even sharks.

Undiscovered Species Of Medicinal Leech Found Hiding In Plain Sight

The FDA approved them as "medical devices" in the U.S. in 2004 to help with blood circulation and wound healing.

Using Leeches to Forecast the Weather

The surgeon George Merryweather had a passion for leeches. According to Merryweather, the creepy worms possessed humanlike instincts, experienced the hollow ache of loneliness, and were capable of forecasting weather. All of this gave him an idea for a machine that he believed could transform meteorology.