Some people have to sneeze suddenly and involuntarily when they step out of dark rooms into bright light, others make fun of it. Often sun sneezing is misunderstood as a symptom of sun allergy. Already Aristotle made considerations to this today as ACHOO syndrome – from its long English name: ACHOO syndrome (Autosomal Dominant Compelling Helio-Ophthalmic Outbursts of Sneezing) – or photic sneezing reflex.
Sunlight and other triggers
The photic sneezing reflex can be triggered by sunlight, but also by other sources. Expressions vary in severity and are thought to affect 17 to 35% of the world’s population, with women more commonly affected than men.
Since time immemorial, people have wondered what triggers the photic sneeze reflex – Aristotle blamed heat, Francis Bacon suggested leaking cerebrospinal fluid as the puzzle solution – and even today, ACHOO syndrome cannot be clearly explained. There is still no clinical diagnosis for ACHOO syndrome.
If both you and close relatives always have to sneeze when you go out of the house on a nice sunny day, you can assume that you have it.
ACHOO syndrome – causes and countermeasure.
It has been thought for several years that ACHOO syndrome is inherited. If one parent has ACHOO syndrome, the children are 50% likely to inherit it.
The most probable explanation is that in ACHOO syndrome “patients” the optic nerve and the triplet nerve, which among other things regulates the nasal mucosa, are too close together. If the optic nerve is irritated by the influence of light, the triplet nerve also reacts and triggers a photic sneeze reflex. The rapid change from light to dark also leads to the photic sneeze reflex in affected individuals.
However, most people with ACHOO syndrome do not sneeze more than three times (but a few people have to sneeze up to forty times), and after the eyes get used to the brightness (usually after 20 seconds), the sneezing reflex subsides. Even sunglasses can help only if the form is mild. There is no other treatment.
A connection between ACHOO syndrome and nasal deviation is also frequently observed. Otherwise, it is assumed that the ACHOO syndrome is harmless – that is why science has not yet put enormous effort into researching the photic sneeze reflex. The only time caution may be needed is on the road, such as when driving out of a long tunnel.
