The vagus nerve, also known as the “wandering nerve,” winds a path all around your torso, intersecting with everything from the heart to the lungs to the digestive tract. That makes it a natural target for a wide range of therapeutic interventions: In the late ’90s, the Food and Drug Administration cleared the first surgically implantable devices to stimulate the vagus nerve, and today they’re used to treat medication-resistant cases of depression and epilepsy.
After weaving its way through your body, the vagus nerve ultimately ends up in your cranium, passing up through your neck and branching off to whisper past the outer edge of your ear. Which is where some companies are hoping they can make an impact without implants.
There are clear signs the FDA is watching their progress. In July, the agency issued an emergency use authorization to electroCore; the company’s handheld device, which was already cleared to treat cluster headaches and migraines by stimulating the vagus nerve on the neck, can now be used to tackle asthma-related breathing difficulties in Covid-19 patients for the duration of the pandemic. In January, the FDA cleared a stim device to treat opioid withdrawal from Spark Biomedical, which is working on a similar approach to help infants undergoing withdrawal.