Cannabinoid Hyperemesis Syndrome: When Marijuana Causes the Vomiting It Usually Prevents

Long-term marijuana use can paradoxically cause severe recurrent vomiting known as cannabinoid hyperemesis syndrome, a condition often misdiagnosed and treated with unnecessary tests and procedures.

Lu, Marvin Louis Roy Y et al.·Cleveland Clinic journal of medicine·2015·Moderate EvidenceReview
RTHC-01002ReviewModerate Evidence2015RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Review
Evidence
Moderate Evidence
Sample
Not reported

What This Study Found

This clinical review described cannabinoid hyperemesis syndrome (CHS), a paradoxical condition where chronic marijuana use causes recurrent severe nausea and vomiting despite cannabis being known as an antiemetic.

The syndrome typically presents with cyclic episodes of vomiting, often accompanied by compulsive hot bathing (which temporarily relieves symptoms). Patients frequently undergo expensive and unnecessary investigations before the diagnosis is recognized.

The only proven treatment is complete cessation of marijuana use. The review emphasized that recognizing CHS can prevent unnecessary medical and surgical interventions in patients presenting with recurrent vomiting of unknown cause.

Key Numbers

Review summarized case report literature; typical presentation involves chronic marijuana use, cyclic vomiting episodes, and relief from hot bathing; only treatment is cannabis cessation

How They Did This

Clinical review article examining published case reports and literature on the pathophysiology, presentation, diagnosis, and management of cannabinoid hyperemesis syndrome.

Why This Research Matters

CHS is increasingly recognized as cannabis use becomes more widespread. Many patients cycle through multiple emergency department visits and undergo extensive testing before the diagnosis is made, creating significant healthcare costs and patient suffering.

The Bigger Picture

CHS challenges the simple narrative that cannabis is universally antiemetic. The condition demonstrates that the relationship between cannabinoids and the gastrointestinal system is more complex than commonly understood, with chronic use potentially reversing the acute antiemetic effect.

What This Study Doesn't Tell Us

Based primarily on case reports and clinical observations. The pathophysiology remains incompletely understood. Prevalence among chronic cannabis users is unknown.

Questions This Raises

  • ?What determines which chronic users develop CHS?
  • ?Is there a dose or duration threshold?
  • ?Could genetic factors predict susceptibility?
  • ?Do different cannabis products or cannabinoid profiles carry different risk?

Trust & Context

Key Stat:
Only proven treatment: complete cannabis cessation
Evidence Grade:
Clinical review synthesizing case report literature. Describes an increasingly recognized clinical entity, though prevalence data and controlled studies are limited.
Study Age:
Published in 2015. CHS has since become much more widely recognized, and hot water bathing has been validated as a clinical clue.
Original Title:
Cannabinoid hyperemesis syndrome: Marijuana is both antiemetic and proemetic.
Published In:
Cleveland Clinic journal of medicine, 82(7), 429-34 (2015)
Database ID:
RTHC-01002

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / ObservationalSnapshot without intervening
This study
Case Report / Animal Study

Summarizes existing research on a topic.

What do these levels mean? →

Frequently Asked Questions

How can marijuana cause vomiting if it is also used to treat nausea?

Acute cannabis use activates CB1 receptors in the brain that suppress nausea. However, chronic heavy use may cause changes in the gut and thermoregulatory system that paradoxically trigger severe vomiting episodes. The exact mechanism is not fully understood.

Why do hot showers help with CHS?

One theory is that hot water corrects a thermoregulatory imbalance in the hypothalamus caused by chronic cannabinoid exposure. Another suggests that redirecting blood flow from the gut to the skin reduces vomiting. The relief is temporary and does not address the underlying cause.

Read More on RethinkTHC

Cite This Study

RTHC-01002·https://rethinkthc.com/research/RTHC-01002

APA

Lu, Marvin Louis Roy Y; Agito, Markus D. (2015). Cannabinoid hyperemesis syndrome: Marijuana is both antiemetic and proemetic.. Cleveland Clinic journal of medicine, 82(7), 429-34. https://doi.org/10.3949/ccjm.82a.14023

MLA

Lu, Marvin Louis Roy Y, et al. "Cannabinoid hyperemesis syndrome: Marijuana is both antiemetic and proemetic.." Cleveland Clinic journal of medicine, 2015. https://doi.org/10.3949/ccjm.82a.14023

RethinkTHC

RethinkTHC Research Database. "Cannabinoid hyperemesis syndrome: Marijuana is both antiemet..." RTHC-01002. Retrieved from https://rethinkthc.com/research/lu-2015-cannabinoid-hyperemesis-syndrome-marijuana

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.