Achoo! How sunshine can trigger a sneeze attack
- Ric Kearbey
- Aug 13
- 2 min read
Updated: Aug 14
If you’ve ever stepped outside into bright sunshine and instantly blasted out a sneeze (or three), congratulations, you might be part of the photic sneeze reflex club. It’s way more common than you’d think, and yes, weather nerds actually study this stuff.
What is going on in your noggin?
The most popular theory on wow sunshine can trigger a sneeze attack says it is all about mixed-up wiring in your brain. When your pupils shrink in sudden bright light, the optic nerve sends a signal.
In some people, that signal accidentally triggers the trigeminal nerve, which is the one responsible for starting a sneeze. It is basically like your brain’s wires crossed and decided, “Sunlight? Must be pepper up the nose.”
The quirky club
Somewhere between 10 and 35 percent of people have this odd reflex, which scientists call the photic sneeze reflex. If you want to impress your friends, you can use the full name: autosomal dominant compelling helio-ophthalmic outburst. That mouthful shortens to ACHOO. Yes, someone clearly worked hard to make that acronym fit.
Is it dangerous?
Not really, unless you happen to be driving, holding a mouthful of soda, or performing brain surgery when the sun hits your eyes. Most of the time, it is just a harmless and funny party trick your brain plays on you.
Can you stop it?
There is no cure, but there are hacks. Some people swear by covering their nose when walking into bright sunlight. Others wear sunglasses to reduce the glare. You can also try closing your eyes for a few seconds when you step outside to avoid the sudden blast of light.
Bottom line
If you sneeze when you step into the sun, you are not allergic to daylight. You just have a brain with a quirky wiring diagram. Now you have a fun fact to pull out during awkward small talk or to amaze someone on a sunny walk.
Comments