Heavy marijuana users may suffer vomiting syndrome, medical experts warn

Medical experts have warned against heavy marijuana usage as there is a growing occurrence of a rare illness that causes vomiting and abdominal pain among users.

The number of reported cases of cannabinoid hyperemesis syndrome (CHS), also known as cyclical vomiting syndrome, are low compared with the overall number of marijuana users.

“When the decriminalization of medical marijuana occurred and the number of medical (marijuana) licenses in some US states went up dramatically, we started seeing more and more cases of young, otherwise healthy people who would have multiple recurrent episodes of severe abdominal pain and vomiting and often end up in the emergency room,” said Kennon Heard, chief of medical toxicology for the University of Colorado Anschutz medical campus in Aurora.

“If you talk to anyone who practices emergency medicine in the state of Colorado, they’re going to tell you they’ve seen this and they see it fairly frequently, and we see it in our emergency department on a daily or weekly basis.”

According to a study, CHS was first discovered in 2004 in Australia, where drug laws are liberal and physicians saw more heavy users of marijuana having bouts of vomiting and abdominal pain that lasted for years. All had been daily marijuana smokers for multiple years and quitting made the symptoms go away.

Only a small percentage of marijuana users had CHS. The Australian study consisted of just nine patients, and Heard’s study identified 36 people with the illness.

Heard says it often takes several hospital visits to confirm it because patients aren’t always open about their marijuana use.

The other major challenge for physicians is that nobody understands how or why marijuana use leads to vomiting or how much marijuana use causes the syndrome.

Heard says long-term use of high-grade marijuana may lead to changes in a system in the body that helps regulate the gastrointestinal tract.

Experts say that users who developed the syndrome had been smoking for years. But there has been nothing found to indicate why some users have CHS and others don’t.

“If you are a heavy marijuana smoker and you have recurring episodes of severe abdominal pain and vomiting, consider whether this could be you and try stopping for a few weeks and see if it helps,” added Heard.