Magnets have a long history as medical devices. Cleopatra is reported to have worn a magnetic lodestone on her forehead in an attempt to forestall the aging process. For decades, magnets have occupied a place among alternative treatments, alongside herbs and acupuncture. Along the way, they also have become big business. Billions of dollars worth of medical magnets are sold each year, over the Web and in Tupperware-style home parties.

Yet as they’ve gained adherents, medical magnets also have fallen into disrepute among many medical professionals.
Several controlled clinical studies conducted in the past few years suggest that magnets may effectively treat some disorders. And a few health-care providers are routinely using magnets for a host of conditions.
A small number of studies have found magnets, either “permanent” magnets or electromagnets, to be effective in relieving certain kinds of pain and hastening wound-healing. Perhaps most significantly, electromagnets are being used experimentally at several university medical schools to treat depression. The procedure is known as transcranial magnetic stimulation.

In transcranial magnetic stimulation, a coil is held next to the patient’s forehead and a pulsating electrical current passes through the coil, generating a magnetic field. That, in turn, creates a small electrical current in the region of the brain called the left prefrontal cortex. That is the area of brain thought to be underactive in depressed people.

Three studies have compared transcranial magnetic stimulation (TMS) to electroconvulsive therapy (ECT), a procedure in which electricity is applied directly to the entire brain. ECT is effective against depression, although it often causes short-term memory loss and other temporary cognitive problems. It gained notoriety after it was featured in the film based on Ken Kesey’s “One Flew Over the Cuckoo’s Nest.”

In the three studies comparing the two procedures, TMS has been as effective as ECT in treating severe depression among people who are not troubled by hallucinations or delusions, according to David Avery, a professor of psychiatry and behavioral sciences at the University of Washington Medical School in Seattle. And ECT, he said, is more effective than anti-depressant drugs.

The studies so far have involved only a couple of dozen subjects. Avery soon will begin a study with about 85 subjects.
Researchers theorize that the magnetic therapy may work by activating sluggish nerve cells in the left prefrontal cortex.

Four years ago, researchers at Baylor University in Houston used magnets to treat muscular or arthritic-type pain in post-polio patients. They laid magnets on the painful areas for 45 minutes.

Seventy-six percent of people treated with real magnets reported feeling significantly better. Nineteen percent of those given sham magnets reported significant pain relief.

In another study, a large group of people with intense nerve pain in their feet — a condition known as peripheral neuropathy and common among diabetics — were given magnetic insoles to wear. A substantial number reported less tingling and burning and numbness in their feet.