The proposed ban on nitrous oxide: political posturing wins out over pragmatic policy


This is a guest blog by cultural historian and author Mike Jay, with additional editing and content by Steve Rolles and George Murkin.

Over the last decade, small silver gas canisters and dew-soaked balloons scattered across the grass have become a familiar dawn sight at the UK’s summer festivals. This was the first visible evidence of the increasing use of nitrous oxide in recreational and dance drug cultures, a trend that now regularly generates media reports of a dangerous new ‘laughing gas craze’ (or ‘hippy crack’ as some lazy journalists like to call it despite no actual users ever using the term). Despite the government-appointed expert Advisory Council on the Misuse of Drugs (ACMD) advising against a ban back in March, it looks as though nitrous oxide will in fact soon be prohibited under the Conservative government’s Psychoactive Substances Bill, which has been widely criticised not only for being futile and counterproductive, but also for being a terribly drafted piece of legislation that will be a nightmare to enforce. 

There is a serious problem with measures to prohibit the supply and use of nitrous oxide. To a far greater extent than most recreational drugs, its health risks are determined by the method of administration. When inhaled via a balloon – the method that has become standard in its current popular form – the risks are relatively minor, and can be effectively addressed by harm reduction information (see below). But when inhaled via a tube or mask – the method associated with its medical use – the risk of death by asphyxiation is considerable, and over the years has claimed a number of lives. A key challenge for a pragmatic, public health-led policy is to prevent this more dangerous form of administration from taking hold, which would be one likely consequence of any effective measures to prohibit the availability of the drug in its current form.


Effects and historical uses

Although nitrous oxide is typically presented as a ‘new’ drug, exploring its effects on consciousness has a long and distinguished history. They were first researched in 1799 by the chemist Humphry Davy, who recorded a brief but vivid intoxication, combining powerful euphoria with distortions of sensation, space and time.[1] In an era before the discovery of psychedelic drugs such as LSD or ecstasy, nitrous oxide remained a focus for research into altered states of consciousness throughout the nineteenth century: eighty years later, the psychologist William James wrote an influential account of his experiences with the gas and their philosophical implications.[2]

During the same era, nitrous oxide also became a popular recreational drug, mostly in the context of variety performances in theatres, music halls and carnivals. In a precursor of the stage hypnotism shows of today, audience members would be invited onto the stage to inhale the gas and encouraged to act out their intoxication in a burst of uninhibited dancing, singing or exuberant laughing. It was in this milieu that its popular name, ‘laughing gas’, first emerged.

It was in the course of these public performances that visiting physicians began to notice that the subject was rendered temporarily insensible to pain, and by the end of the nineteenth century nitrous oxide, along with ether and chloroform, was being widely used as an anaesthetic in dentistry and general surgery. At this point the gas, thus far produced by the potentially explosive reaction of heating ammonium nitrate, became commercially available in pressurised tanks, from which it was administered via diaphragms and surgical masks. This allowed the delivery of a continuous supply of gas, enabling patients to be maintained in an unconscious state for longer surgical procedures. Hallucinations and unconscious ‘automatisms’ of speech or reflex action were commonly noted as side effects.[3]

The recreational use of nitrous oxide was rediscovered by the emerging drug culture of the late 1960s, particularly in the USA. Tanks of gas were ‘liberated’ from their medical use for Hollywood poolside drug parties, and the Grateful Dead took to carrying one on their tour bus. But this first wave of recreational use was limited: firstly by the expense and logistical problems presented by acquiring a large tank of compressed gas, and secondly by the emerging realisation that it was very easy to pass out while inhaling from a surgical mask and die from asphyxia. After the well-publicised death in 1974 of Hollywood producer Artie Ross by such a misadventure, the recreational use of nitrous oxide diminished.[4]


The current wave of recreational use

The current wave of nitrous oxide use has developed around a different method of administration: via small canisters or bulbs of the gas, sold by catering suppliers for producing whipped cream (and, less often, for some other foamed-food concoctions by inventive modern chefs). These are similar to the bulbs of carbon dioxide used in soda siphons, but nitrous oxide is preferred since carbon dioxide is acidic and causes cream to curdle. As with soda siphons, the bulbs are supplied with a dispenser into which, when fitted, they release their compressed gas. If the dispenser is filled with cream, the gas, released under pressure, converts it to a foam which can then be squeezed out of the dispenser nozzle. If the dispenser is empty, however, the nozzle simply releases the gas that has been discharged into it. A balloon can be placed over the nozzle to capture the nitrous oxide as it is released, and the gas then inhaled from the balloon. Small metal devices called ‘crackers’, sold online and in headshops, can also be used to fill the balloon directly from the canister.

This delivery system of dispensers, bulbs and balloons has made nitrous oxide more accessible to recreational users than ever before. An initial outlay of around £40 secures a dispenser, after which bulbs can be purchased, in packs of ten or twenty, for around 50p each. The effects of inhaling a balloon are brief but intense: a rush of euphoria and heightened consciousness that peaks within a minute of inhalation, and subsides rapidly as the lungs refill with atmospheric air and the nitrous oxide leaves the blood stream, in the same way that carbon dioxide does. These effects are dramatically heightened by other mind-altering drugs, particularly cannabis, MDMA and psychedelics such as LSD or magic mushrooms, and nitrous oxide use has typically taken hold in ‘party’ scenes where these drugs are being used socially. In this context it heightens feelings of dissociation and excitement and, in an echo of its nineteenth-century theatrical use, tends to promote exuberant laughter. Users who enjoy these effects may enter into an initial period of heavy use during which they explore them intensely, usually in the company of others; but this period is typically brief, tailing off once the limits of the experience have been tested. The most commonly observed pattern of use, therefore, is one of enthusiastic immersion followed by a longer career of occasional use in social or party situations.

This type of use has been spread by word of mouth over the last decade, with use mostly taking place in private homes, though it has gradually become more public and visible. From the late 1990s, balloons of nitrous oxide were occasionally being sold in dance clubs, particularly those with psychedelic, trance and ambient sound systems, and up until the clampdown (following the clarification of the law in 2007) sellers offering balloons became a common sight at summer festivals. Prevalence of use in the UK has risen considerably in recent years: 470,000 people used nitrous oxide in 2013/14 – up by about 100,000 on the previous year. As with all drugs, it is most popular among young people, with 7.6% of 16-24-year-olds having tried it in the last year. That’s compared to 4.2% for cocaine, 3.9% for ecstasy and 1.8% for ketamine.


Harm reduction and regulation

Nitrous oxide is not without health risks. It lowers blood pressure, and those who are susceptible to this may experience fainting or unpleasant sensations of dizziness and weakness, comparable to the ‘whitey’ effects that can be provoked by a large dose of cannabis. Like all mind-altering drugs, it can have negative and destabilising effects on subjects with present or incipient mental health problems, and in a minority of users it can produce disturbing automatisms such as unconscious vocalisations and uncontrolled muscular activity (one of the reasons it is becoming less favoured in surgical anaesthesia[5]). Cases of ‘addiction’ have occasionally been recorded, and have long been anecdotally familiar among dentists and anaesthetists; but although the urge to repeat the experience can become compulsive, there is little evidence for true metabolic addiction (tolerance of dosage or physical withdrawal). The health harm common to all users is that the gas selectively oxidises folate, or vitamin B12, and a session of heavy use will deplete all stores of this vitamin in the body.[6]

But by far the most serious health risk is asphyxiation from passing out while the mouth and nose are connected to a tube or surgical mask. The volume of nitrous oxide offered by a balloon is far lower than an anaesthetic dose, and the user is unlikely to lose consciousness; if they do, most commonly from holding the gas in the lungs for too long and not breathing enough oxygen, the balloon will simply fall from the mouth, and they will begin breathing atmospheric air and recover. With a tube or mask, however, far larger doses can be inhaled, and users will, if they continue to inhale pure nitrous oxide, gradually drift into unconsciousness. If the tube or mask is not removed at this point, unconsciousness will be succeeded by oxygen starvation and death. This was the cause of the first recorded death by nitrous oxide in the current wave: in September 2006, a young company director from the West Midlands, Daniel Watts, was found dead beside a large medical tank of nitrous oxide, with a tube in his mouth and a plastic bag over his head.[7] When used as a medical anaesthetic, in childbirth or dentistry for example, nitrous oxide is mixed with oxygen, (a 50%-50% mix called Nitronox, Entonox or just ‘gas and air’), so can be taken safely for a longer continuous period without risk of asphyxiation.

Daniel Watt’s death highlights the fact that the dangers of nitrous oxide are closely linked to its method of administration. Inhalation via small bulbs and balloons eliminates the risk of such tragic accidents and, because this is the form in which the current wave of recreational use has developed, users perceive the health risks of nitrous oxide as low. In this sense, balloons represent an effective harm reduction strategy.

For this reason, however, there are real risks in attempting to overly restrict the availability of nitrous oxide. The obvious route will presumably be to restrict sales of bulbs and dispensers from catering suppliers, although quite how such a ban on nitrous oxide bulbs – already in widespread use for catering (non-drug) use – will be implemented in practice remains to be seen. There is a risk that such a move would lead to an increase in the far more dangerous use of large tanks and surgical masks (although balloons can of course still be filled from tanks, and hopefully, as the now established method of use, this would remain the norm). 

As so often with prohibitions introduced after demand has already been established, there is also a likelihood that rather than being eliminated, the market would simply default to criminal vendors selling via the many thriving online markets for illicit drugs or diverting catering supplies. Nitrous oxide is a product with many industrial uses and many commercial sources: other forms, such as the tanks used for engine fuel in drag racing, can contain toxic adulterants. Illicit diverted supply would make it substantially more likely that users would be exposed to these risks. The population of nitrous oxide users who have been using the gas in relatively safe ways would therefore be exposed to more dangerous products, dangerous criminal markets, and potentially far more dangerous methods of administration. These increased risks may also be poorly understood by users themselves; fatal accidents with tanks are most common among such inexperienced and uninformed users.

Thus far, in the pronouncements of public health professionals in the media, the dangers of nitrous oxide have been conflated with those of asphyxiation in general,[8] generating deterrent advice about the ‘new craze’ which lacks credibility with users. Official health warnings have thus far failed to draw attention to the specific dangers of tanks and masks, and have shown a poor grasp of the chemistry and physiology involved. In 2007, the Medicines and Healthcare Products Regulatory Agency (MHRA) issued a press release, which despite its claim to ‘robust and fact-based judgement’, asserted incorrectly that ‘the ‘rush’ users experience is caused by starving the brain of oxygen’. As Ben Goldacre, writing in the Guardian, commented:

‘To be effective in public health policy, it is generally considered that your message must be credible. I suspect most [nitrous oxide] users will already have experimented with holding their breath, and will rightly conclude that their experience on nitrous is a drug effect; and that it’s an anaesthetic used in hospitals, and in childbirth, so the effect is probably not caused by starving the brain of oxygen; and that the MHRA, of all reputable bodies, is talking nonsense.'

A strategy focused on public health outcomes would, therefore, need to consider carefully the risks and possible ‘unintended consequences’ of any attempt to overly restrict supply in its current form. The potential harms of nitrous oxide use might be better managed by a credible information campaign that stressed the dramatic differential in risk between different forms of administration, as well as highlighting the health issues associated with nitrous oxide use in general. The essential messages might include the following:

Nitrous oxide: Health risks and harm reduction
  • Always inhale nitrous oxide from a balloon - never from a tube or mask, or directly from a dispenser or compressed air tank
  • Never inhale while standing up: always sit or lie down, and be aware of your immediate surroundings (e.g. steep drops, fires, open water)
  • Always put out cigarettes or joints before inhaling, and spit out chewing gum
  • Don’t take nitrous oxide if you have problems with low blood pressure, or any mental health issues
  • If you feel any physical discomfort, such as pins and needles or numbness, stop inhaling
  • Take vitamin B supplements after a session

The long-term policy solution to managing the risks of nitrous oxide, and the other drugs covered by the Psychoactive Substances Bill, is responsible, evidence-based legal regulation – not ill-considered, populist prohibitions. As the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) has said today, banning so-called 'legal highs' will simply drive the trade underground; it won’t eliminate it. According to the EMCDDA’s scientific director, the evidence from countries where blanket bans were introduced was that despite an immediate impact on availability as headshops close down, in the medium to long term, the trade simply moved online or onto the streets.

This is what officials in Poland say has happened since they imposed such a ban five years ago. Additionally, while the country saw a sharp decline in the number of reported poisonings from legal highs shortly after the introduction of the ban, three years later the number of poisonings has rebounded, and is now above pre-ban levels. If that wasn't enough, the futility of this supposedly ‘tough’ approach is even more stark when prevalence figures are considered. The country with the highest last-year use of legal highs in Europe? Ireland… where a blanket ban has been in force since 2010.


[1] Humphry Davy, Researches Chemical and Philosophical, Chiefly Concerning Nitrous Oxide (J. Johnson 1799), see Mike Jay, The Atmosphere of Heaven (Yale 2007)

[2] William James, On some Hegelisms, in Mind 7: 186-208 (1882), see Mike Jay, Emperors of Dreams: drugs in the nineteenth century (Dedalus 2011).

[3] For accounts of hallucinations under dental anaesthesia, see Antonio Melechi (ed.), Mindscapes: An Anthology of Drug Writings (Mono 1998)

[4] See Peter Biskind, Easy Riders, Raging Bulls: How the Sex’n’Drugs’n’Rock’n’Roll Generation Saved Hollywood (Bloomsbury 1998)

[5] Another reason is emerging evidence that it can impact on post operative homocysteine levels that may increase risk of adverse cardiac events; myocardial ischemia and, possibly, myocardial Infarction. See Myles PS, et al Nitrous oxide and perioperative cardiac morbidity (ENIGMA-II) Trial: rationale and design.Am Heart J. 2009 Mar;157(3):488-494.e1.

[6] For a summary of clinical research on nitrous oxide’s effects, see Diana J. Walker and James P. Zacny, Subjective Effects of Nitrous Oxide, in Mitch Earleywine (ed.) Mind-Altering Drugs (Oxford University Press 2005)

[7] See Clubbers’ laughing gas craze claims its first life, Sunday Times 4/2/2007

[8] See Sunday Times, ibid.