Electric stimulation may reduce inflammation by ‘hacking’ the nervous system

A new method that stimulates the vagus nerve with electrical impulses has shown promise in reducing chronic inflammation, with researchers calling it a potential “brake” on the immune system, Swedish public broadcaster SVT reports.

The technique, already approved in the US for treating severe rheumatoid arthritis, involves implanting a small device that delivers short daily electrical pulses to the vagus nerve—a major nerve connecting the brain to key organs. Studies suggest this can curb the overproduction of inflammatory substances by immune cells.

“You could say we’re hacking the nervous system to suppress excessive inflammation,” said Jon Lampa, professor of rheumatology at Karolinska Institutet.

The implanted device, activated for just a few minutes per day, has demonstrated long-lasting effects on immune cells, according to Peder Olofsson, professor of bioelectronic medicine at Karolinska Institutet. Reported side effects so far include minor surgical infections and temporary hoarseness during activation, though long-term data is still limited.

Researchers are now exploring whether external stimulation—delivered via the ear—could achieve similar results without surgery. A Swedish study testing this approach on rheumatoid arthritis patients is underway, with preliminary feedback from participant Linn Frostmats Broberg describing reduced inflammation and pain, as well as eliminating her need for strong painkillers.

“This could revolutionise treatment for chronic inflammatory diseases,” Olofsson said, noting the method’s potential as an alternative when medications fail or cause severe side effects. Clinical use in Sweden, however, may still be 5–10 years away, according to Lampa.

Ongoing trials are also investigating vagus nerve stimulation for multiple sclerosis and Crohn’s disease.