ACHOO syndrome causes uncontrollable sneezing from sunlight, camera flashes, and more. Evidence suggests that scientists have been trying to understand the cause as far back as 350 BCE.

Some sneeze when they see bright light, called a photic sneeze. It is also known as the ACHOO syndrome, and some researchers believe it runs in families. Hatham Djippers, 27, who lives in Oregon ...

This is a phenomenon known as Photic Sneeze Reflex. Another name is Autosomal dominant Compelling Helio-Ophthalmic Outburst syndrome. Yep, that spells "ACHOO", and some call it "ACHOO Syndrome".