Sneeze reflex: facts and fiction.

Sneezing is a protective reflex, and is sometimes a sign of various medical conditions. Sneezing has been a remarkable sign throughout the history. In Asia and Europe, superstitions regarding sneezing extend through a wide range of races and countries, and it has an ominous significance. Although sneezing is a protective reflex response, little else is known about it. A sneeze (or sternutation) is expulsion of air from the lungs through the nose and mouth, most commonly caused by the irritation of the nasal mucosa. Sneezing can further be triggered through sudden exposure to bright light, a particularly full stomach and physical stimulants of the trigeminal nerve, as a result of central nervous system pathologies such as epilepsy, posterior inferior cerebellar artery syndrome or as a symptom of psychogenic pathologies. In this first comprehensive review of the sneeze reflex in the English literature, we aim to review the pathophysiology, etiology, diagnosis, treatment and complications of sneezing.