Laughing gas 'can cause paralysis', warns Wales' top doctor

Laughing gas is "not just a bit of harmless fun" and can cause paralysis, Wales' chief medical officer has warned.

Nitrous oxide - as it is also known - is the second most commonly used recreational drug in the UK after cannabis for those aged 16-24.

Chief medical officer Dr Frank Atherton said the costs of misuse can be "astronomical".

"We see people who are no longer able to walk or use their arms or legs."

He added: "Sadly that can be irreversible."

Although it is illegal to sell nitrous oxide - or 'nos' - for the purposes of recreational use, it is legal to sell it for catering and medicinal use.

Twenty-year-old Connor (not his real name) used to inhale laughing gas on a regular basis.

He said the "buzz" he would feel lasted for about 30 seconds so "when you do one, it could be a minute after that and you want another one, and then another one".

'Numbness, tingling... and paraplegia'

Prof Gino Martini, chief scientist at the Royal Pharmaceutical Society, and Dr Amira Guirguis of Swansea University Medical School have been working together to raise awareness of the dangers.

"We think that what happens is that chronic use of nitrous oxide stops you absorbing vitamin B12," said Dr Martini.

"If you get a depletion, it erodes this protective covering and it damages your spinal cord.

"That's why we see people get issues like numbness, tingling, problems with walking, and in severe cases paraplegia, which is a type of paralysis."

• How dangerous is laughing gas?

• 'Don't be complacent over laughing gas risks'

• Websites 'must block illicit nitrous oxide sales'

Dr Atherton is concerned that young people don't know enough about the potential risks.

"I think the challenge is to get information to people to help them to understand that it is not just a harmless bit of fun. There are potentially significant consequences, particularly for people who are heavy users," he said.

"Even if you have just one case of paralysis... the lifetime costs of that to society, let alone the personal cost to that individual, are absolutely astronomical."

Nitrous oxide - the highs and lows

• Effects include euphoria, calmness, dizziness, difficulty thinking straight, giggling and hallucinations

• Inhaling nitrous oxide from the canister or in an enclosed space - like with a bag over your head - is very dangerous

• By inhaling nitrous oxide the user risks falling unconscious or suffocating from lack of oxygen. People have died this way

• If someone collapses after using nos, turn them on to their side, call 999 and stay with them until an ambulance arrives

Source: Frank

Eye On Wales is on air on Wednesday, 14 October at 18:30 BST on BBC Radio Wales and BBC Sounds.