The 18-year-old woman, named by newspapers as Gaby Scanlon, complained of breathlessness and gastric pain before being rushed to a hospital in the northern English city of Lancaster on Thursday where she was diagnosed with a perforated stomach.

Scanlon is currently in serious but stable condition, local police said in a statement over the weekend.

"Medical opinion is that this would have proved fatal had the operation not been carried out urgently," police said.

When exposed to air, liquid nitrogen creates a dense fog and is used by bartenders and chefs to add an element of visual drama to dishes or to freeze things quickly, such as ice cream.

It is also used for removing warts and has industrial uses. Contact with flesh can cause cryogenic burn or "frostbite".

Professor of food physics at Leeds University Malcolm Povey said liquid nitrogen should not be consumed while still liquid, as it turns into a gas inside the body and causes the stomach to swell and burst.

"The liquid nitrogen would rapidly change into gas and blow the stomach up like a balloon...the idea that people put this stuff in drinks is just unbelievable," Povey told Reuters.

The bar which served the drink has stopped selling all liquid nitrogen drinks, said police, who are investigating the incident. (Reporting By Alessandra Prentice, editing by Paul Casciato)

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