When sitting in a quiet theatre or a packed train, stifling a sneeze by holding the nose and closing the mouth may seem like the courteous option.

当你坐在安静的剧院或拥挤的列车上时，用捂鼻子或紧闭嘴巴的方法把喷嚏憋回去似乎是个有礼貌的选择。

But doctors have warned against the polite practice, after a man ruptured the back of his throat while trying to contain the convulsive explosion of air.

The 34-year-old was admitted to hospital barely able to swallow or speak after pinching his nose and clamping shut his mouth to stop a sneeze.

When doctors examined him they also heard strange popping and crackling sounds, which extended from his neck all the way down to his ribcage.

A scan confirmed that that air from his lungs had bubbled its way into the deep tissue and muscles of the chest when it could not escape.

Ear, nose and throat specialists at the University Hospitals of Leicester NHS Trust released details of the man’s condition in BMJ Case Reports and warned that trying to contain a forceful sneeze could lead to ‘numerous complications’ and even a lethal brain aneurysm.

"Halting sneezing via blocking the nostrils and mouth is a dangerous manoeuvre, and should be avoided," said lead author Dr Wanding Yang.

"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).”