With cases of flu continuing to rise in Canada, there's likely a whole lot of "achooing" going on across the country. But ear, nose and throat doctors advise against trying to stifle those sneezes, as such suppression can in rare cases lead to injuries.
One of the most serious is detailed in the journal BMJ Case Reports, published online Monday, in which a 34-year-old man from the United Kingdom ruptured his throat after pinching his nose and clamping his mouth shut to contain a forceful sneeze.
The post-sneeze trauma left the man in pain and barely able to speak or swallow.
When emergency care doctors examined the patient, they heard popping and crackling sounds extending from his neck to his rib cage -- a sign that air bubbles had found their way into the tissue and muscles of his chest, the authors at the University Hospitals of Leicester NHS Trust write.
The unidentified man, who was treated in hospital for a week, was advised against repeating such a "dangerous manoeuvre" in the future.
"This tear in the throat is incredibly unusual," said Dr. Douglas Chepeha, an ear, nose and throat (ENT) specialist at University Health Network in Toronto. "In my career, I've never seen anything like that."
However, he said there are a number of other injuries that could occur from trying to block a sneeze, though they, too, are relatively rare.
Impeding the release of air from the nose and mouth during a sneeze could rapidly increase the pressure in the lungs, forcing the air out and trapping it in the chest between the lungs -- a condition known as pneumomediastinum.
A suppressed sneeze could also build up pressure in the middle ear, though Chepeha said bursting an eardrum that way is very rare. (To understand the effect, think of popping one's ears in a descending airplane by breathing out against pinched nostrils to restore hearing.)
In the BMJ case report, authors point out that thwarting a sneeze -- the body's attempt to eliminate such irritants as mucus or allergens in the nose -- could conceivably rupture an undetected aneurysm, or ballooning blood vessel, in the brain.
And it could also cause small surface blood vessels in the eyes and other areas of the head and neck to burst due to built-up pressure, Chepeha said.
"In your nose itself, you can burst a blood vessel and get a bleeding nose."
Even without being impeded, sneezing has been known to cause injuries, said Dr. Eric Monteiro, an ENT at Mount Sinai Hospital in Toronto.
"There have been reports of elderly women who develop brittle bones in osteoporosis, developing vertebral compression fractures as a result of sneezing," he said Monday in an interview.
Some Major League Baseball players have hurt themselves by sneezing, including Toronto Blue Jay Kevin Pillar, who ended up on the 10-day disabled list when a sneeze led to an oblique muscle strain during the 2015 pre-season.
So is there a right way to sneeze?
Not really, said Monteiro, explaining that sneezing is an involuntary protective reflex that can't necessarily be controlled.
"But I think there is a wrong way, which is trying to plug your nose and close your mouth, which is just generally not recommended because you inhibit the natural process," he said.
"And if you do that, you're potentially setting yourself up for an injury, notwithstanding the fact that they're rare."
While doctors may discourage people from stifling a sneeze -- whether it's a dainty achoo or a big honk -- Chepeha said people should deliver it into their inner elbows to prevent spreading the flu virus or other air-borne bugs.
"Of course you have to cover your mouth, and the absolute best way is to cough or sneeze into your sleeve."