sneeze

A sneeze, or sternutation, is a rapid, forceful expulsion of air from the lungs through the nose and mouth, prompted by irritation of the nasal mucosa. It is a reflex that involves the trigeminal nerve and other pathways, coordinating respiration, facial muscles, and the glottal opening to produce a sudden expulsion of air.

Common triggers include irritants such as dust, pollen, smoke, and strong odors; viral or bacterial infections; allergic rhinitis; changes in temperature or humidity; and, in some individuals, bright light provoking the photic sneeze reflex.

Sneezes often occur singly but may come in bursts of two or more. In social settings, people commonly sneeze into a tissue or the elbow to limit spreading droplets; if possible, avoid sneezing into hands. Suppressing a sneeze can increase pressure and cause discomfort or injury in rare cases.

Most sneezing is harmless and serves to expel irritants. Persistent or unusual sneezing with other symptoms may indicate allergies, infections, or nasal obstruction and warrants evaluation. Treatments target the underlying cause and may include saline irrigation, antihistamines, decongestants, or nasal corticosteroids.

Sneezing occurs in many animals, including most mammals, and is a common defensive reflex to clear the nasal passages.