Magnet Therapy Side Effects and Warnings

Safety Issues

In general, magnets appear to be safe; the biggest risk appears to be irritation from tape holding them in place. MRI machines, for example, expose the body to gigantic magnetic fields, and extensive investigation has found no evidence of harm. However, during the MRI, the patient is subjected to a high level of magnetism for a short period of time, whereas people who use static magnets daily or sleep on them every night are subjected to a low level of magnetism over a long period of time. So far, it is not known whether this type of exposure has any deleterious effects. Nonetheless, one study, in which participants slept on a magnetic mattress pad every night for 4 months, found no side effects. ¹ In addition, a safety study of rTMS found no evidence of harm. ² In a large study in which rTMS was administered to numerous depressed patients, totaling over 10,000 cumulative treatment sessions, no significant adverse effects were reported. Transient headache and scalp discomfort were the most frequent problems reported. There were no seizures, nor changes in hearing or cognition. ³ It was previously thought that people with implantable cardioverter defibrillators (ICDs) and pacemakers should not use magnetic devices at all, but this recommendation has been adjusted. One study found that with the exception of magnetic mattresses and mattress pads, most magnets sold for therapeutic purposes do not interfere with the magnetically activated switches present in most pacemakers. Magnetic mattress pads can deactivate and alter the function of ICDs and pacemakers, but other therapeutic magnets are safe if kept 6 inches or further from these devices. ⁴ There are theoretical concerns that magnets might be risky for people with epilepsy. Similarly, until the physiological effects of magnet treatments are better understood, pregnant women should avoid them.