One patient found that the only way he could keep his food down was by eating all his meals in the bathtub.
Another refused to leave the shower, since that was the only place he wasn’t tortured by constant nausea, and ended up being dragged out by paramedics after his parents called an ambulance.
One thing they had in common: both were heavy marijuana smokers. Another: they suffered from ‘cannabinoid hyperemesis syndrome,’ a condition in which some people who use a lot of pot suffer from endless nausea and intense abdominal pain.
Raj Waghmare, a doctor who works in the emergency ward in Southlake Regional Health in Newmarket, Ont., says he encounters about one case over the three shifts he works a week, and that the hospital as a whole sees “a couple hundred cases a year”.
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“Patients come in, and they have severe, epigastric pain (in the upper abdomen),” he says. “It’s an unrelenting pain, often associated with quite a bit of vomiting – retching, nausea. What sets it apart from stomach flu, which can cause the same thing, is that it really doesn’t respond to pain medications.”
Cannabinoid hyperemesis syndrome wasn’t identified until 2004, when doctors in Australia identified the cause and gave it a name.
The syndrome seems to have increased in U.S. states that have legalized recreational marijuana.
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(A Facebook group focused on the condition has over 750 members.)
Doctors have learned to diagnose the problem — they look for heavy marijuana use and stomach pain and nausea that are only relieved in the bathtub or shower — but they don’t really understand how it works, or why hot water helps.
“It’s this whole striking thing that a hot bath makes it better. I don’t lead them into it, I say: ‘You have these symptoms – is there anything that makes it better? ’ Often patients will volunteer it up, and say ‘If I sit in a hot bath.’”
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The problem has only been seen in very heavy users: “Often these patients are using a couple of times a day, every day. Not the occasional once or twice on a weekend or every second weekend.”
Quitting marijuana fixes the problem, but often not immediately. Some literature says it only takes a day or two, but Waghmare has known it to take months.
That’s all very well for recreational users, who can end a real problem by giving up a hobby.
But it’s harder for medical users, some of whom started using marijuana in the first place to control nausea. Waghmare thinks that marijuana may have the ability to both induce and stop nausea.
“I’m not saying that marijuana doesn’t help with nausea. I think it does.”
“It actually works on those nausea receptors. But then those receptors get sensitized to the point that their behaviour reverses. It’s the same receptors that end up causing the nausea. Initially it does work, it works on those receptors and helps with patients’ nausea, but then the effect kind of reverses itself.”
What isn’t at all clear is why some heavy marijuana users have the problem and others don’t. (One group of doctors suggests there’s a genetic component.)
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It’s unknown in some countries, which suggests it may be caused somehow by how some marijuana is produced. But with at least some of Canada’s pot still coming from illegal, shadowy supply chains, it’s hard to probe further.
“It could be something that’s in the marijuana here – that it’s being grown differently, or treated differently.”
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