What Is Cannabinoid Hyperemesis Syndrome? A New Study Figured Out How Many People Puke After Smoking Weed & It’s More Common Than You Think

With recreational use of marijuana now permitted in eight states and the District of Columbia, more people than ever are (legally) getting their hands on weed. And though there's still plenty of debate over just the health benefits of marijuana for our bodies, a recent study has shown that one proven negative effect of weed, called cannabinoid hyperemesis syndrome (CHS), is more common than you might think.

Cannabinoid hyperemesis syndrome is a mouthful of a name for a nasty side effect. To put it bluntly, it's when you vomit after smoking marijuana. Folks who have CHS can also experience nausea and stomach pain to go along with their severe vomiting, Insider reported. The new study, which comes from emergency clinicians at New York University Langone and was recently published in the journal Basic & Clinical Pharmacology & Toxicology, says CHS may affect as many as 2.75 million Americans.

According to the study report, CHS is often classified as a "rare" or "very rare" syndrome, and it wasn't even named until 2004, when a study examining 10 people who experienced "a very upset stomach in connection to frequent, heavy marijuana use," according to Insider. One patient examined in the study was an Australian woman. When she joined the study, she'd been experiencing "sudden and severe episodes of illness for nine years. She'd get nauseous [sic] and feel like the room was spinning, which was followed by violent vomiting and severe stomach pains," Insider reported.

It turned out Mrs. X had also figured out a homemade balm to ease her then-unnamed syndrome: A hot bath. "[H]er symptoms seemed to melt away into the warm tub," according to Insider. In the newly published study, hot water soothing symptoms was a crucial part of officially diagnosing people who took the study's questionnaire. Researchers gave questionnaries to people between the ages of 18 and 49 who said they smoked marijuana at least 20 days per month. According to the study report, patients who smoked at least 20 days had to also rate "hot showers" as "five or more on the ten-point symptom relief method Likert scale for nausea and vomiting" in order to be classed as having suffered from CHS.

Overall, the study looked at 155 patients, and 32.9 percent of those "met our criteria for having experienced CHS," the study report said. Extrapolating those numbers allowed researchers to hypothesize that 2.75 million Americans may also suffer from CHS.

A story from CNN published before the release of this study cited CHS as an "obscure syndrome [...] only recently acknowledged by the medical community," but one that was, in December 2017, on the rise after the legalization of recreational marijuana use in California and Colorado, according to emergency physicians in the states.

Unfortunately, data from the new study doesn't include a potential treatment aside from warm water. "Doctors can do little to relieve the symptoms, since traditional anti-nausea medications often don't work and there are no pills to prevent the onset of an episode," CNN reported. "Patients may need intravenous hydration and hospital stays until the symptoms subside."

Joseph Habboushe, an assistant professor at NYU Langone and the lead author on the recent study, told Insider that helping people with CHS can be especially tricky because the only thing that can truly make CHS subside is quitting marijuana. "And many patients will stop for a few days, and it goes away, but then they start smoking again and it comes back."

Habboushe added that he's "concerned," but that this emerging information about the prevalence of CHS "doesn't mean marijuana is bad or good it [sic] just means it has side effects — side effects that we need to understand and learn how to avoid and treat."