ACHOO Syndrome: Why You Sneeze When You Look at the Sun

There’s just something about a sunny day that makes you feel … like sneezing? That’s a reality for a surprising number of people with a condition known as ACHOO syndrome. They literally sneeze when they see the sun or any other bright light.

So, why does this happen and what can be done about it? We talked to allergist Dylan Timberlake, MD, to find out.

What is ACHOO syndrome?

ACHOO syndrome is a reflex in which a person sneezes once or a few times when suddenly exposed to bright light, especially sunlight. Basically, it’s an exaggerated response to something that shouldn’t cause issues.

And the funny name? Well, ACHOO is an acronym for a wordy and more formal title — Autosomal dominant Compelling Helio-Ophthalmic Outburst.

The condition is also known as photic sneeze reflex, as well as sun sneezing and photosneezia.

Why does bright light make people sneeze?

Typically, a sneeze is a response to some sort of nasal irritation. Examples include infections, congestion or nose-tickling triggers like pollen or pepper.

But a sun-driven sneeze originates in your brain. Exposure to a bright stimulus seems to activate a sneeze pathway in your brain that runs between nerve circuits around your eyes and nose.

“These circuits ‘cross-talk’ with each other and convince your brain a sneeze is needed, even though it’s not,” explains Dr. Timberlake. “The reaction is typically immediate and short-lived. Once you sneeze, it’s over — at least until the next exposure.”

Typical photic sneeze reflex triggers

ACHOO syndrome usually strikes on initial exposure to the sun or very bright light. It’s most common when moving from a darker to a lighter environment, like walking outside or driving out of a tunnel.

A camera flash or turning on bright indoor lights can bring on sneezing, too.

How common is ACHOO syndrome?

While sneezing at the sight of the sun might sound odd, it doesn’t appear to be that unusual.

It’s estimated that 18% to 35% of us have ACHOO syndrome. (Higher than you thought, right?) But there aren’t many robust studies on the photic sneeze reflex, so there’s debate about the numbers.

An older study found that solar sneezing is more common in people who are white, especially women. Having a deviated septum may also be a contributing factor.

Is photic sneeze reflex genetic?

ACHOO syndrome is a dominant genetic trait, which means you have a 50% chance of inheriting the condition if one of your biological parents has it.

Can ACHOO syndrome be dangerous?

The act of sneezing after your eyes catch a glimpse of bright light isn’t inherently dangerous. But what is dangerous is sneezing uncontrollably in high-risk situations that need focus, like when you’re driving.

That sort of bad timing happens, too: One case study documented a 26-year-old involved in THREE crashes linked to sunlight-induced sneezing fits.

“Uncontrollable sneezing can cause problems or be inconvenient in certain situations,” notes Dr. Timberlake. “You certainly wouldn’t want it to happen when you’re behind the wheel or operating heavy machinery.”

Other dicey moments created by ACHOO syndrome include sneezing during eye or dental procedures due to bright light usage. (We probably don’t need to explain why that could turn out badly.)

Some photic sneezers also react to certain kinds of anesthesia given for procedures.

Given the above, Dr. Timberlake says it’s important to let your healthcare providers know that bright lights may trigger sneezing before they start procedures. (Anesthesia use may make you more sensitive to a photic sneeze reflex, too.)

Is there a cure for photic sneezing?

There’s no specific treatment for ACHOO syndrome, but Dr. Timberlake says there are three different tactics that may be worth trying to reduce bouts of solar-powered sneezing.

• Wear dark sunglasses. A good pair of shades can make sudden exposure to sunlight less dramatic, which may prevent a reaction. Hats or other accessories may do the trick, too.
• Address allergies. Successfully managing nasal inflammation in photic sneezers with hay fever sometimes reduces the tendency to sneeze.
• Apply pressure. Pushing down on the area between your nose and lips can sometimes stop the sneezing. If you’re doing it right, it should look like you’re giving yourself a mustache with your finger. This is known as the “transverse philtral pressure technique.”

“Managing ACHOO syndrome is mostly about knowing your triggers and being prepared,” says Dr. Timberlake. “You know that a sneeze might be coming in certain situations. It’s best to be ready for it.”