When it comes to sneezes, it seems there's a golden rule: better out than in. This has been somewhat painfully demonstrated by a man in the UK, whose attempt to hold in a sneeze resulted in a trip to hospital with a ruptured pharynx.
A sneeze is the body's method of clearing an irritation out of the air passages, and they can often happen without warning.
They're also pretty explosive, reaching measured speeds of up to 16.2 kilometres per hour (4.5 metres per second, or 10 miles per hour).
Obviously there are times when sneezes feel inappropriate, and most of us will have tried to stifle one at some point - but it's not an easy thing to do.
To try and keep his sneeze from erupting, the 34-year-old patient went to extreme measures, clamping his mouth shut and pinching his nose closed with his hand.
His neck immediately swelled up, and not long after, he started finding it extremely painful to swallow and all but lost his voice, said doctors from the University Hospitals of Leicester NHS Trust.
Rupture of the pharynx - the passageway of the throat leading from the mouth and nose to the oesophagus and larynx - is very rare, usually caused by trauma, and on rare occasions by vomiting, retching or heavy coughing. Initially, the doctors were somewhat taken aback.
However, when they examined the patient, they discovered popping and crackling noises all the way from his neck to his ribcage.
As you might remember from the girl who screamed so loud at a One Direction concert that her lung collapsed, this symptom is called crepitus, caused by air bubbles popping under the skin.
In the case of this patient, they were in the deep tissue and muscles of his chest, caused by the rupture in his throat.
This type of injury isn't exactly unheard-of - in 2011, doctors in Boston in the US reported the case of a 38-year old man who had also pinched his nose and closed his mouth to stop a sneeze. In that instance, his actions resulted in a fractured larynx.
As those doctors noted, preventing a sneeze from escaping in that manner allows the pressure of the sneeze to peak at over 38 times the pressure of a normal sneeze. It's like being punched in the throat by your own violent exhalation.
The UK man was kept in hospital under observation because of the risk of complications, tube-fed and administered intravenous antibiotics until the swelling and pain had subsided. He was discharged after seven days.
The doctors urge, however, that you just let sneezes happen. Vigorous sneezing can result in air getting trapped in the soft tissues around your eyes, but that's much less dangerous than having your throat swell up. Also, it's extremely rare.
"Halting sneezing via blocking nostrils and mouth is a dangerous manoeuvre, and should be avoided," the doctors wrote in the case study.
"It may lead to numerous complications, such as pseudomediastinum [air trapped in the chest between both lungs], perforation of the tympanic membrane [perforated eardrum], and even rupture of a cerebral aneurysm [ballooning blood vessel in the brain]."
The case report has been published in the BMJ Case Reports.