Recurring episodes of nausea, vomiting, and severe abdominal pain. Compulsive bathing. You might not think of these as potential consequences of regularly using cannabis—especially given that it’s known to have anti-nausea effects in people undergoing chemotherapy.
But they are in fact classic signs of cannabinoid hyperemesis syndrome (CHS), a puzzling gastrointestinal condition that’s associated with frequent, long-term use of marijuana.
First described in 2004 by doctors in Australia , CHS affects an estimated 2.75 million people in the U.S. each year, and cases are rising: According to research in an October 2024 issue of JAMA , emergency department visits related to CHS doubled in the U.S. and Canada from 2017 to 2021.
( Do you smoke weed recreationally? Here’s what experts want you to know .)
What’s behind the rise? It may be partly because marijuana is now easier to access, thanks to the broadening legalization of cannabis for recreational use. Research supports this notion. In a 2024 study published in the Journal of Clinical Gastroenterology , researchers compared hospitalizations for CHS at a large hospital in Massachusetts in 2012 and 2021, before and after cannabis was legalized in the state: They found a significant increase in hospitalizations.
Another factor: “The cannabis that’s available now is much more potent than what was available 30 years ago,” says Deepak Cyril D’Souza, a professor of psychiatry at the Yale University School of Medicine and director of the Yale Center for the Science of Cannabis and Cannabinoids. In the 1960s, the potency of delta-9-tetrahydrocannabinol (THC), the psychotropic component in marijuana, was typically 2 to 4 percent, D’Souza notes, whereas these days the concentration of THC can be 18 to 35 percent or higher.
Still “why some people seem to be vulnerable to this and not others really seems to be a mystery,” says D’Souza. Here’s what researchers are unraveling about this curious condition. The perfect gift for the history buff in your life. Give now and get a FREE TOTE BAG. LIMITED TIME OFFER
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The biggest risk factor for CHS is heavy cannabis use, as in almost daily or […]
This strange syndrome is linked to regular cannabis use—and cases have doubled
