Sneezing is the powerful expulsion of air in response to irritation. Here are some common and not so common causes of sneezing.
Achoo! Everyone experiences the forceful expulsion of air more commonly known as a sneeze, but what really causes sneezing to occur? At the most basic level, sneezing is a protective mechanism that evolved to shield the lungs from foreign particles. Causes for sneezing include the obvious ones such as the common cold or allergies, but also include less common medical conditions – some of which can be serious.
What Causes the Sneezing Reflex to Occur?
People sneeze when their nasal passages are exposed to particles or debris that causes irritation. Nerves present on the skin lining the nasal passages are triggered by foreign debris. This sends a signal from the trigeminal nerve to the sneezing center of the brain – a part of the medulla. The brain sends back a signal to prepare for a sneeze and a forceful breath is taken in – followed by the expulsion of air and a characteristic “achoo”. The number of particles expelled in a single sneeze is around 40,000.
Common Causes for Sneezing
The most common causes for sneezing are inflammation of the nasal passages due to the common cold virus or allergies. These conditions are usually associated with a runny nose and stuffiness too. Some people sneeze in response to irritants in the air such as dust, perfume, or cigarette smoke. This is the body’s attempt to protect itself from foreign substances.
Less Common Causes for Sneezing
Some people experience a phenomenon called the photic sneeze. This is where sneezing occurs in response to looking at a bright light such as the sun. This is likely to occur if a person stares straight up at the sun or if a bright light is suddenly shone in their eyes. It’s estimated that about twenty-five percent of the population are photic sneezers and this tendency seems to run in families.
Another strange cause of sneezing is the snatiation reflex. This is a sneeze that occurs when the stomach is distends after eating a large meal. Snatiation sneezing may come in bursts which may be distressing to the victim. This sneezing reflex also runs in families.
More Serious Causes of Sneezing
Sneezing can also be triggered by certain brain diseases such as epilepsy and from anatomical abnormalities in the brain. Another less common cause of sneezing is withdrawal from opiate medications which not only causes excessive sneezing, but a runny nose as well.
The Bottom Line?
For the most part, sneezing doesn’t indicate any serious pathology, but is simply the body’s reaction to irritation. According to history, the Greeks and Romans considered sneezing to be a sign of good health. Keep that in mind the next time you let out a loud one.