Sneezing is reflex reaction that usually occurs with the common cold, flu, inhaling an allergen or even just tickly dust irritating the inside of your nose. Either way, the point of a sneeze is to try and get whatever’s bothering the inside of your nose out!
WHAT CAUSES SNEEZING?
When you breathe in, you take in more than oxygen. You can breathe in dust, allergens, bacteria and viruses floating around in the air.
Sometimes something you breathe in will irritate the inside of your nose. Things like dust or dirt will tickle the mucus membranes that line your nose and throat. Whatever irritating thing you breathed in will stimulate nerves inside your nasal passage. Signals are then sent to your brain to trigger a reflex reaction (a sneeze).