The second set of guidance relates to transcutaneous electrical stimulation of the supraorbital branch of the trigeminal nerve (above the eye) for treating and preventing migraine.16 This applies to the Cefaly external trigeminal nerve stimulation (eTNS) device.17

The battery-operated headband device delivers controllable small electric currents from electric pads positioned above the eyebrows. The user should use the device for 20 minutes each day for prophylaxis, but may also find benefit in acute migraine attacks.16

With the evidence base still limited, NICE’s recommendations for NHS use are similar to the vagus nerve stimulator device.

Cefaly has indicated that the device may help reduce migraine symptoms by 40-50 per cent. The mode of action is still uncertain, but studies in Italy have found that the trapezius muscle in the neck and the frontalis muscle on the forehead “showed a significant decrease in tension. In addition, increased activity was recorded in the anterior temporalis and auricularis posterior muscles which sit around the ear, indicating a ripple-like effect across the head and neck from the site of the Cefaly neurostimulation.”18

Another small study noted episodic migraine sufferers have a lower level of metabolic activity in the front temporal regions, but after three months of using the device, activity increases to the ‘normal’ levels seen in the control group.19

Responses from over 460 regular Cefaly users has suggested a further benefit: a new study has reported a reduction in acute migraine medication usage, potentially helping reduce the longer term risks of medication overuse.20