This article originally appeared in the November 2004 Harvard Health Letter and is provided courtesy of Harvard Health Publications.

Leeches and maggots: Not appealing, might help with healing

The blood-sucking leeches and flesh-eating maggots you might see in a horror movie are moonlighting these days in hospitals and doctors’ offices —with the FDA’s blessings, no less.

Doctors have found that leeches can help skin grafts and reattached body parts mend. “Medical maggots” are being promoted for the treatment of wounds and skin ulcers. In June 2004, a French company received FDA approval to market leeches as a “medical device.” Six months earlier, the federal agency gave maggots a green light.

This is a comeback for both creatures. From antiquity until the late 19th century, bloodletting with leeches was used to treat all sorts of illnesses and infections, often with disastrous results. The intent was to purge the body of bad blood.

Using maggots to help heal wounds goes back a long way, too. The Mayan Indians employed them. Napoleon’s chief military surgeon noted that wounds infested with maggots sometimes healed faster, and during World War I, an American surgeon, W.S. Baer, made the same observation. Baer went on to promote maggot therapy with some success after the war, but it fell out of use with the discovery of sulfa drugs and penicillin.

Relax. This is a pretty limited comeback, not a return to the bloodletting’s heyday. Sometimes blood pools under a skin graft or around a body part that has been surgically reattached. The trapped blood can cause pain, increase the risk of infection, and block blood flow through veins. Doctors have had success using leeches to suck it out.

Maggots are hardly front-line therapy, either. The medical term for removal of excess dead tissue from a wound is debridement (pronounced de-BREED-ment). Keeping a wound moist and covered encourages the body’s own enzymes to debride by breaking down dead tissue biochemically. Doctors can surgically do the job by cutting or scraping away dead tissue. But sometimes these and other measures fail. Maggots, which are flies at a larval stage, have a taste for dead flesh that makes them champion “debriders.” Better yet, the blowfly maggots used for wounds are picky: They avoid live tissue and dine on the dead stuff.

Maggot therapy’s biggest booster is Dr. Ronald A. Sherman of Irvine, Calif. He has set up a nonprofit organization, the Biotherapeutics Education and Research Foundation, to promote maggot and other forms of “biotherapy.” We’ll keep an open mind, but we’re not quite ready for the ichthyotherapy mentioned on the foundation’s Web site. It’s defined as “wound-eating fish” therapy.