There is not much good evidence about how well transcutaneous stimulation of the cervical branch of the vagus nerve for cluster headache and migraine works, but there are no major safety concerns. It should only be used if extra care is taken to explain the risks and extra steps are put in place to record and review what happens.
More research on this procedure is needed and NICE may look at it again if more evidence is published.
Your health professional should fully explain what is involved in having this procedure and discuss the possible benefits and risks with you. In particular, they should explain the uncertainty about the evidence on how likely it is to improve your symptoms. You should also be told how to find more information about the procedure. You should only be asked if you want this procedure after having this discussion. Your health professional should ask you if details of your procedure can be collected.