From Science:
Bloodsucking leeches relieve the pain of thumb arthritis more effectively and for a longer period of time than the conventional painkilling ointment, according to new clinical trial results. The findings, presented here yesterday at the North American Research Conference on Complementary and Integrative Medicine, may move leech treatment one large wriggle closer to the mainstream of medicine.
Osteoarthritis of the thumb afflicts millions of people, causing joint pain debilitating enough to keep them from opening jars, writing notes, and gripping anything tightly. Doctors usually prescribe painkilling pills, injections, or ointments, but none of the treatments work well. Internist Gustav Dobos of the University of Essen in Germany, and his colleagues had successfully treated patients’ arthritic knees with leeches before. The worms inject a blood-thinning chemical called hirudin and several substances that fight inflammation–components that keep a prey’s blood flowing in the wild.
More here.