Non‐inasive vagus nerve stimulation—Hope or hype?

The vagus nerve is the tenth and longest of the cranial nerves, whose course runs from the brainstem to the splenic flexure. It is the main neural substrate of the parasympathetic nervous system and has both afferent and efferent pathways, although the former predominate (80%). An increasing body of evidence has demonstrated it has a central role in modulating gastrointestinal pain, inflammation, and motility. Within this issue of the Journal, Gottfried‐Blackmore and colleagues report the results from an open‐label pilot study examining the role of non‐invasive vagus nerve stimulation (VNS) in idiopathic gastroparesis. This mini review provides a contemporaneous summary of the current methods by which non‐invasive VNS can be achieved, its potential indications within the field particularly with respect to gastroparesis. In addition, this review also addresses some of the pitfalls and propose the outstanding questions which may inform and guide the future research agenda.