Using the principle of transcutaneous electrical nerve stimulation (TENS), the device is a headband that delivers small electrical impulses to branches of the trigeminal nerve, a nerve responsible for facial sensations and motor functions. The trigeminal nerve is also implicated in migraine attacks.
The results of a clinical study using the Cefaly headband showed that study participants experienced significantly fewer days with migraines per month and used less migraine attack medication. For people who tend to have adverse side effects from migraine medications, a TENS headband could be a useful alternative.
An important note: in the clinical trial, the headband device did not reduce pain when a migraine attack was already in progress, so this approach isn’t a cure-all for migraine symptoms.