I suffer from a rare ACHOO syndrome that causes me to sneeze in direct sunlight – but I thought everyone did this?

A woman has shared the unusual genetic condition and many people were surprised to discover that they suffer from the same syndrome.

Sarah Allison from the US often sneezes when exposed to bright light, usually direct sunlight, due to a unique syndrome aptly called ACHOO.

She said it happens a few times a day, especially while driving, and thought everyone did the same before learning it only affects 17 percent of the population.

“Do you want to see this weird genetic condition I have that only about 20 percent have? Let me show you,” Sarah said online video.

She walks from the inside of her house to outside into the sunlight and immediately feels the need to sneeze.

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Sarah explained that the phenomenon is called ACHOO, which stands for Autosomal Dominant Compelling Helioopthalmic Outburst.

“Which means light activates a photoreflex, which means I sneeze when I see light,” she said. This usually happens in direct sunlight.

‘I thought everyone did that. Sometimes when I’m driving I start sneezing and can’t stop. It doesn’t happen every time I’m exposed to direct sunlight, but it happens a few times a day.’

ACHOO syndrome has a number of names, including sneezing in the sun, photic sneeze reflex, photoptarmosis, and even photosneezia.

Sarah explained that the phenomenon is called ACHOO, which stands for Autosomal Dominant Compelling Helioopthalmic Outburst

The reflex is most common in intense sunlight when moving from a dark to a light environment, with some even responding to a camera flash, according to the Cleveland Clinic.

It is caused by crossing of wires over the trigeminal nerve, a facial nerve that goes to your eye and nose.

Sarah’s clip was viewed more than 10 million times on her social media channels, as many people were told but unaware that sneezing in the sun was a real syndrome.

‘Only 17 percent? I literally don’t know a person who doesn’t do this,” one viewer responded.

“Wait, you’re telling me it’s not normal,” wrote a second.

‘Doesn’t everyone do this?? Because my kids and I do it all the time,” one mother added.

“I thought I was the only one and joked that I was allergic to the sun,” another user laughed.

‘I have it, but it only works when I feel a sneeze struggling to come out. Look at sunlight and I’ll sneeze,” one woman said.

Others were amused by the ‘appropriate’ name of the condition, with one saying: ‘I like that they called it ACHOO… they didn’t have to do that, but they did.’

“The fact that they named it to match the acronym ACHOO is insane,” another joked.

Many with ACHOO syndrome recommend wearing sunglasses outdoors because sneezing does not pose a risk to anyone’s health, but can be dangerous during activities such as driving.

‘I have this too! That’s why I wear sunglasses all the time. As an older millennial, I’ve noticed very few eye lines and wrinkles, so it’s a double duty,” one person suggested.

‘Sunglasses prevent this. So wear them while driving. Definitely helps!’ another agreed.