As country moves to legalize, Canadian study looks at possible rise of marijuana illness

Cannabinoid hyperemesis syndrome (or CHS for short) is a condition that consumers may experience over multiple times following smoking sessions

While some may see cannabis as a benign substance, a new study from researchers in Canada all but confirms that some marijuana consumers may face a mysterious illness after ingesting cannabis.

Cannabinoid hyperemesis syndrome (or CHS for short) is a condition that consumers may experience over multiple times following smoking sessions, and symptoms include cyclical nausea, vomiting, and abdominal pain.

The condition often prompts sufferers to visit an emergency department, as the symptoms can become unbearable. The study identified almost 500 individuals who entered emergency departments that were suffering from nausea and vomiting, finding that among the regular cannabis users (defined by the study as more than three times a week), 92% of the sufferers received IV fluids and had bloodwork done, and 43% of them had repeat emergency visits for similar symptoms.

CHS is a condition that is not well-known; the study itself says that cannabinoid hyperemesis syndrome can often be an “overlooked diagnosis” for nausea and vomiting.

It has received a bit more attention in Canada in recent times, however, as CBC News reported on one sufferer’s condition back in November of 2016.

At the time, the subject of the story, Dawn Rae Downton, told CBC news that she’s “afraid that people are walking into trouble” when they start taking medical marijuana, adding that “I want to protect people, I want to warn people.”

Earlier that year, CTV News did its own story, with a patient named Dave who said that he was a 25-year marijuana smoker and recently began to suffer from these symptoms. He spoke live on CTV National News, saying it was hard to find doctors in Ontario that had a specialty in the condition, and that he began to feel better only three to four weeks after he stopped smoking (he also suspected that it might have had to do with the shatter he had begun to smoke at the time).

The study, published in the Canadian Journal of Emergency Medicine, found that CHS may not be screened for in patients who come into emergency departments. “When did you last smoke marijuana,” isn’t a question you often hear in the emergency room, but the study suggests that emergency departments screen for cannabis use and possible CHS when a patient presents with relevant symptoms.

While the study doesn’t speak to how common CHS is with cannabis consumers, the lack of clinical data and research illuminates how rare it might be. Still, the Canadian government would be wise to study the condition and include warnings about it alongside cannabis sales so that consumers and their health care providers can identify it as it happens. And it would be a prudent step for the Canadian government to take; CBC reported last year that according to one expert, in “American states like Colorado, where marijuana is legal, hospitals are reporting a spike in the number of people reporting cyclical vomiting conditions.”

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  1. Doctor Biochemistry Reply

    It's called Azadrachitin poisoning, it's well known that neem oil exposure causes these symptoms. Every symptom you're describing is an allergic reaction to the acute ingestion or exposure of said allergen or antigen (one of the main triterpenoids in neem known as Azadrachitin). Clearly, the unregulated cannabis from dispensaries doesn't adhere to the strict regulatory guidelines by Health Canada for screening of insecticides, pesticides and herbicides. When I purchase cannabis from the black market or dispensaries I suffer from this issue. On the other hand, when I purchase from tweed I don't. Bad science is finding correlation between a popular causation and to coming said conclusion a.k.a confirmation bias.

    1. Maxcatski Reply

      I have always resisted using neem oil even though it is recommended for a number of issues with cannabis plants. For sure, I will never use it now after the Doctor's comments. I have never experienced Cannabis Hyperemesis Syndrome (CHS) and I hope I never will. Is neem oil the sole cause of CHS? I don't know but I do know that the only way to ensure the purity of your cannabis is to produce it yourself. Legalization of medical cannabis in Canada has gone a long way to improve quality but we're not there yet. In the meantime, I am happy to have a clean and trustworthy source for my cannabis.

  2. Sandra Colasanti Reply

    I think this could be more related to pesticides than actual cannabis itself. Recent information coming out of Colorado is starting to confirm this.