When Vito Oliveri first tried nitrous oxide in his twenties he didn't expect a legal drug that gives a quick high to temporarily paralyze him and his fiancée years later, leaving them unable to walk their four dogs.
As recently as early last year, Oliveri, 34, who lives in Portland, Oregon, near some of the best ski resorts in the US, would often ski or take trips to the lakes with his fiancée, Emily Shuford, 30.
"I'd typically be on the mountain on a Monday like today, but we just can't. Emily uses a cane and I probably can't walk a mile. We've been limited to the house, probably since April of last year," Oliveri told Insider in February.
Nitrous oxide, also called "laughing gas" or "hippie crack," is used as a painkiller during labor and for whipping cream in catering. But it's grown in popularity as a recreational drug in the US, Australia, and Europe in recent years, with people inhaling it for a relaxed, giggly, euphoria that lasts, on average, one to two minutes.
Experts have become increasingly concerned about nitrous oxide and its potential harms, particularly amid the rise of super-size stainless steel canisters, which came onto the market in around 2017 to "deliberately target" recreational users, according to a recent European Monitoring Centre for Drugs and Drug Addiction report.
"Maybe once every five or six years, I'll see a patient who's had a stroke from taking cocaine. Yet, every week, I'm seeing this in my ward. So from my point of view, this is actually a bigger problem," Dr. David Nicholl, a consultant neurologist at Sandwell and West Birmingham NHS Trust, UK, told Sky News on March 1.
When Oliveri first took the drug, he attached a silver lipstick-sized capsule containing 0.2 ounces of nitrous oxide to a whipped cream dispenser and filled up a balloon that he inhaled the gas from. He liked it right away.
Oliveri said that while the "little crackers" can taste bad, the bigger cylinders are more convenient, tasteless, and produce stronger euphoric effects.
Nitrous oxide can paralyze people because it destroys nerve cells within the spinal cord by inactivating vitamin B12, which is essential for maintaining the lining of the nerves, Alistair Noyce, a consultant neurologist working in a London hospital in the UK, told Insider.
That nerve damage can also cause tingling and numbness of the affected body part, with the severity of symptoms depending on how extensive the damage is, according to Noyce, who is also a professor at the Preventive Neurology Unit at the Wilson Institute of Population Health, Queen Mary, University of London.
People can also lose their balance because signals that tell the brain where body parts are positioned don't get transmitted properly, Noyce.
Oliveri, who has trouble balancing from the nerve damage caused by nitrous oxide, falls over when his dogs jump on him or pull their leash. He now sends two of his dogs — a chocolate Labrador and German Shepherd — to doggy daycare once a week so they get enough exercise.
Oliveri shared his story to raise awareness of the dangers of using nitrous oxide.
"There's a warning on alcohol bottles, there's a warning on cigarettes that tell you what's going to happen but for nitrous oxide, there's nothing," Oliveri said.
It's legal to possess nitrous oxide in most countries, but some have criminalized supplying it for recreational purposes.
The Netherlands recently banned its possession and sale over concerns about nerve damage and traffic accidents from people driving high, and the UK, where its illegal to sell but not to possess, could soon follow.
In the US, New York state banned its sale in 2021, partly because of the risk of abuse, and in California recreational use is a misdemeanor.
While it's rare for people who don't use the drug often or in low quantities to get nerve damage, Noyce said he'd seen patients experience it after one use but he doesn't know if those cases happened at random or if they were susceptible for some reason.
Noyce said he'd seen people, mostly in their teens and twenties, at the hospital who were "really very disabled" from using high quantities of nitrous oxide, needing to use a walking frame or wheelchair, and others who were incontinent or unable to get an erection.
Noyce said that there isn't an agreed definition of "heavy use," but a ballpark figure is using more than 10 to 15 canisters more than once a week, citing his own research, while the Dutch Poison Centre classes puts it at inhaling 50 or more balloons in a single session.
Users who develop symptoms like numbness, unexplained incontinence or problems with erections should stop taking it, immediately seek help, and tell a doctor that they use the drug because prompt treatment with vitamin B12 injections is "crucial," Noyce said.
"Some recover, some don't," he said.
Oliveri first tried the drug when he was 26 years old, partying with co-workers on a cannabis farm in California, before he met Shuford.
He took it at parties for about a year and stopped until he moved to Portland in 2020 and discovered the super-size cylinders containing 20 pounds of nitrous oxide — equivalent to 1,600 0.2-ounce capsules — and costing around $400 each.
As the cylinders weren't available in his area, he'd use 400 to 500 canisters a day for about a year to achieve the same euphoric effects.
"As soon as they run out you're like, ah, I need more," he said.
Noyce believes that the super-size cylinders are more dangerous than canisters, in part because it's easier to take large quantities. People turn a valve on the big cylinders to fill a balloon, rather than having to screw a tiny canister onto the end of a dispenser and awkwardly twist each time.
Shuford first tried a small canister of laughing gas during the couple's first Christmas together, after they met at a cannabis dispensary in 2018, and she instantly liked it, too.
However, it wasn't until June 2021 when a company started selling super-size cylinders from 10am to 10pm daily in Portland that they started using the drug heavily, unable to stop for weeks at a time.
The couple bought cylinders to feed their cravings, even when they wound up in hospital, unable to walk from nerve damage.
According to Noyce, nitrous oxide isn't physically addictive in the same way that drugs such as heroin are, but can cause "an element of psychological dependence."
"Patients endorse that they crave it when they're not taking it, they're irritable, they're constantly chasing the same original feeling that they got and that leads to higher and higher quantities," he said.
Oliveri said that the couple shared around two super-size cylinders a day for weeks at a time, only pausing if they vomited or experienced flu-like symptoms.
"The high only lasts 10 to 15 seconds and then your mind just wants to do it again," Oliveri said.
As well as health issues it landed them in financial trouble. Oliveri said that the couple could spend up to $1,300 in a day.
Over six or seven months Oliveri said they spent $20,000 on a credit card and another $50,000 cash.
Their savings gone, Oliveri now works for a delivery service.
Oliveri first noticed something was wrong in April 2022 when his legs started uncontrollably shaking and he struggled to stand still. Unknown to him, this was a sign of nerve damage from nitrous oxide.
A month later, the couple used two super-sized cylinders before a flight to Mexico, and Oliveri's legs became so shaky that he had to hire an automated chair to get around the resort.
By June 2022, the pins and needles were "extreme." One day he woke up numb from his belly button down and couldn't walk.
He was with Shuford, but had to ring a friend to help carry him to the car and drive him to the local hospital, where doctors said that nitrous oxide had damaged his nerves and treated him with vitamin B12 injections.
Oliveri said that it was eight weeks before he could move around the house with a cane, and then another five weeks to walk without it, though his ankles still "don't work completely" so, like his other friends that use the drug, he "hobbles."
Oliveri said it was his supplier who first told him that the drug could inactivate B12, after he noticed Oliveri "wobble walking."
"Prompt treatment with B12 injections probably offers the best chance of recovery but won't protect you if you carry on using," Noyce said. Some people try to supplement with vitamin B12 tablets to try to prevent themselves from coming to harm, but Noyce said that's not thought to work.
The couple tried to stop using the drug after Oliveri got home but couldn't. Five months later, in November 2022, Shuford was hospitalized for 17 days because she couldn't walk. It took six weeks of physical therapy before she could walk without a cane.
The couple again tried to quit, and they did for a month, but would get stressed or bored and start to crave its euphoric effects.
Speaking after a recent three-day binge, Oliveri said that he felt "pretty upset" about using the drug because it's hard for him to walk again. The couple can't fully flex their ankles up or down, or move their toes properly, but are doing exercises to try to improve that.
As of March 16, the couple hadn't touched the drug for a few weeks.
"We're gonna try to really be done now, we are able to walk now so we gotta stay ahead of it," he said.
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