Sneezing, or sternutation, is an abrupt, involuntary and forceful expulsion of air through the nose and mouth. This involuntary reflex, triggered by the trigeminal nerve, is the body's attempt to ...

There's nothing more frustrating than not being able to sneeze when you feel like you have to let one out. While a big sneeze can be jarring and a little messy, it's completely normal bodily function.