Niesbuien

Niesbuien, commonly known as sneezing, is an involuntary expulsion of air from the nose and mouth. This reflex is typically triggered by irritation of the nasal mucous membranes. When irritants such as dust, pollen, pepper, or animal dander come into contact with the sensitive lining of the nose, nerve signals are sent to the brain, which then initiates the sneeze reflex.

The process of a sneeze involves a deep inhalation followed by a forceful exhalation. The eyes are usually closed during a sneeze, and the mouth and nose are opened. This reflex serves to clear the nasal passages of the offending substance. Sneezing can also be triggered by changes in temperature, bright lights (a phenomenon known as photic sneeze reflex), or even strong emotions.

While sneezing is a natural bodily function, frequent or persistent sneezing can sometimes indicate underlying health conditions. Allergies are a common cause of recurrent sneezing, where the immune system overreacts to normally harmless substances. Viral infections, such as the common cold, also frequently cause sneezing as the body tries to expel the virus.

The act of sneezing itself is generally harmless, though it can spread germs. It is advisable to cover one's mouth and nose when sneezing, preferably with a tissue or the crook of the elbow, to prevent the transmission of airborne particles.