Penalties for selling nitrous oxide for recreational use have increased, but some say it's a big move for our least harmful drug.
People have been using nitrous oxide to get an instant high since the 1700s, but it is only recently that alarm about rising cases of serious harm has prompted governments, including New Zealand's, to crack down on its sale and use.
But drug researchers say it is the wrong approach to tackling our least harmful drug and education is the best way to prevent serious and lasting damage.
English chemist Joseph Priestley discovered the euphoric effects of synthesising nitrous oxide (N2O) in 1772, calling it "phlogisticated nitrous air", according to the British Medical Bulletin, and by the end of that century it became the drug of choice for the British upper classes.
It is still a party drug today, popularly called nangs or NOS and typically sold in small canisters at local dairies. Max Phillips, head of Students for Sensible Drug Policy in Dunedin, says its attraction is it is easy to access, and that it provides a quick hit from cracking open the canister or bulb, filling up a balloon with the gas and inhaling it.
"You'll get an overwhelming sense of euphoria, [and be] pretty much unable to stand or move your body whatsoever. Effectively you've been lifted up into the sky and don't have a body anymore for that very short 30-second period," he says.
It is growing awareness of its dangers, including that paralysing effect and B12 depletion from overuse that can cause nerve damage in the brain and spinal cord, that has led to pressure for tougher regulations.
On 22 September, Medsafe changed its advice on N2O which means that when it is sold primarily for the purpose of inducing a psychoactive effect, the Psychoactive Substances Act 2013 applies. Under that act, all nitrous oxide products are illegal, with penalties of prison for up to two years for an individual caught selling them or a fine of up to $500,000 for a company.
One worrying aspect, says Medsafe in a statement to The Detail, is the increased appearance of large canisters, sometimes containing one to two litres of gas, which considerably increases the risk of misuse and harm when inhaled.
"The risks from abuse of such large amounts include potentially fatal side effects, particularly since breathing in large quantities of nitrous oxide means you are depriving yourself of oxygen for potentially long periods of time, or life-long neurological damage.
"This is not taking into account the risks from misusing nitrous oxide while operating heavy machinery, driving, or other high-risk activities which can become more dangerous while incapacitated."
Medsafe says it has been monitoring "alleged misuse of nitrous oxide" and cites a study by Auckland City Hospital that highlights a "growing harm issue for New Zealand".
Otago University psychology lecturer Ryan Ward says the changes are an overreaction and highlights the failings of the government's national drug policy.
"The level of harm being experienced doesn't justify a sweeping crackdown on the drug."
He says increasing the penalties will not stop people using it illegally but will drive it further onto the black market.
"You're not dealing with a drug like methamphetamine or heroin or cocaine that doesn't necessarily have any kind of legitimate use.
"You can make whipped cream with it, you use it in high performance vehicles - and people use it recreationally.
"The sticking point, I think, for me and for my colleagues and for other people who are concerned about this change is how do you at the point of sale discern intent of use. It's not easy to do and so what's going to end up happening is people who use nitrous are going to be pushed further into the shadows and we known what happens when drug use takes place under those circumstances, when it is stigmatised by society, is actually the harms associated with that use are amplified."
Phillips says a lot of people use nangs at parties or musical festivals while under the influence of other drugs because the nitrous oxide can intensify the sensation without dangerous side effects.
"All drug use is actually on the rise, really and that also means... we're going to see more instances of people who have long term, or addicted - to use a loose word - kind of relationships with nitrous oxide. And that means we're going to see more people present to emergency departments," he says.
But that is no reason to crack down on its sale, he says.
"It really means we have failed to educate people on nitrous oxide."
He thinks it should be available for sale in shops where consumers are made aware of the risks associated with overuse.
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