Authorities issued an urgent warning yesterday after a 19-year-old man was taken to hospital with serious facial injuries on the weekend after playing the "choking game" with friends at Stockton.

It is understood a female friend held the man in a stranglehold as part of the bizarre game aimed to achieve a brief feeling of euphoria brought on by cerebral hypoxia, or depriving oxygen to the brain for a short period.

Ambulance officers were called to an address in Mitchell Street following a report of a man not breathing who had fallen face first on a concrete floor.

It is understood he suffered several broken facial bones.

The "game" has gained notoriety in the United States where it has been blamed for at least 82 deaths among children since 1995.

Teenagers who spoke to The Herald about the game this week said it was commonplace at some parties and was known to take place in school toilets.

Sophie, 15, of Carrington, said she knew many friends that had participated in the game, with herself reporting a "tingling feeling" and "some bruising" afterwards.

"It is something that people do to try out I suppose," Sophie said. "It's like an experiment for most of us really.'' Another teenager said she knew a friend who had used his mobile phone to film the game, also known as the "pass-out game'', "fainting game'' or "space monkey'', with the intent of putting the footage on YouTube. Both said it was common for participants to drink alcohol before hand and there were several different ways to "play the game''.

Pediatric emergency specialist at John Hunter Hospital Dr Mark Lee issued a strong warning yesterday against taking part in the "foolish game''. Dr Lee said participants could suffer seizures, stroke, cardiac arrest, brain damage or death. "Essentially what you are doing is blocking off the blood flow to the brain, cutting the oxygen and nutrient supply,'' Dr Lee said. "It is very dangerous and death could be the outcome . . . it's playing with fire and you could kill yourself.''

Child psychiatrist Louise Newman said the "choking game'' was similar to other sorts of "risk-taking behaviour'' in youths. Dr Newman said the aim was to experience an "extreme emotional high'' and she said many youths would not be fully aware of the dangers.

She warned teenagers against taking part but said it was vital those who did should call for immediate medical assistance in the event of a problem.

"There is always a lot of peer pressure for young people and it can be very hard to resist,'' Dr Newman said. "Young people need to say that it's not for them and they don't want to take part in it ... if it does take place, there needs to be an emphasis on getting medical help if they are concerned.''

Department of Education spokesman Sven Wright said the "choking game'' had not been raised as a major issue in the Hunter. Mr Wright said students or parents aware that the game was taking place should report the incidents to their school and immediate action would be taken.