Blowing your nose seems like something you should be able to do without worrying you're going to hurt yourself. After all, facial tissue and pocket handkerchiefs exist for the express purpose of having something to blow snot into, right? But, depending on how vigorously you blow, clearing out your nose might not be as safe or hygienic as it seems.
You might be called to blow your nose for a variety of reasons — your excess nasal mucus may be due to a cold, a sinus infection (sinusitus), allergies or because you've been crying all day on account of a perfectly natural existential crisis. Whatever the reason, you're uncomfortably stuffed up and you want relief. But what are the dangers of covering your nose with a tissue and honking?
1. Fractured Bones
Your face is full of tiny little bones — think about skulls you've seen before. The bones around your eye sockets and the sinus and nasal cavities, for instance, are exquisitely thin. Because significant nasal congestion puts that whole area under a lot of pressure, the delicate scaffolding that holds your face up might not be able to withstand the stress.
"Although this is extremely rare, prolonged and repeated vigorous blowing could lead to stress fractures, just as ribs can fracture from similar repeated and prolonged coughing," says Dr. David King, a senior lecturer in the Medicine Program at the The University of Queensland in Australia. "Both vigorous coughing and nose blowing generate high pressures in their respective cavities."
2. Sinus or Ear Infection
According to one 2000 study, the fluid dynamics of nose blowing are such that mucus is propelled from the nasal cavity into the sinuses. The study didn't go so far as to test whether this was particularly harmful, but the bacteria in the snot itself could certainly jumpstart a sinus infection. Similarly, aggressive nose blowing could send bacteria to the inner ear, resulting in an ear infection.
3. Ruptured Eardrum
It's extremely rare to rupture an eardrum while overenthusiastically clearing your schnoz, but the rapid change of pressure behind the eardrum can indeed cause the eardrum itself to burst. So, take it easy on the old hanky, okay? And if you're recovering from a broken eardrum, it's best to lay off blowing altogether.
4. Nose Bleeds
There are hundreds of tiny blood vessels in the nose and sinuses, and blowing your nose too hard or too frequently can sometimes result in one or more of them rupturing, especially when conditions are dry or when the lining of the inside of the nose is already extra sensitive due to a cold. These nosebleeds aren't usually dangerous (unless there's a pre-existing condition compounding the problem — if you're taking blood thinners, for example), and will generally heal quickly, but nobody likes a bloody nose.
5. Worst-case Scenarios
Nightmare scenarios associated with blowing your nose are extremely rare, but sometimes people end up at the hospital with a severe headache after blowing so hard that air is forced into the space between the skull and brain. A study published in the May 5, 2015, issue of The Journal of Pediatrics has shown that nose blowing can result in air entering the space between the two lobes of the lung as well. It has also been known, on occasion, to rupture the esophagus.
How to Properly Clear the Snout
So, how does one deal with nasal congestion when the time-tested method seems to have medical drawbacks?
First, let's be honest: You're not going to stop blowing your nose altogether. Since that's the case, it's a good idea to blow out gently, focusing on one nostril at a time. But how do you know if you're being gentle enough?
"There is no particular threshold that's considered hard or forceful blowing of the nose, so the question about knowing if you're blowing too hard doesn't have a simple answer," says King. "However, the force required to move air through a tube — the nasal passages — is increased if the diameter is reduced. So blowing the nose to relieve congestion is not the best way to deal with this symptom."
King suggests instead starting a treatment to deal with the causes of the congestion.
"Congestion under the skin of the nose is effectively treated with decongestants sprays or tablets for short treatment durations, or treating the underlying cause of more ongoing conditions with antihistamines or steroid sprays," he says. "Congestion due to thick mucus that contributes to narrowing of the nasal opening is best treated by saline nasal sprays or washes."