A Case of Cannabinoid Hyperemesis Syndrome: The Cyclical Vomiting That Only Hot Showers Relieve | Research

The takeaway

A case report highlights cannabinoid hyperemesis syndrome (CHS), a condition in heavy daily cannabis users characterized by cyclical vomiting, nausea, and abdominal pain that resolves only with hot baths or stopping cannabis use.

Readers who use cannabis daily and experience unexplained nausea or vomiting.

CHS resolves only with cannabis cessation; hot bathing provides temporary relief

What the researchers found

The case describes the clinical presentation of cannabinoid hyperemesis syndrome, a condition increasingly recognized in emergency departments as cannabis legalization expands. The hallmark features include severe cyclical nausea and vomiting, recurrent epigastric or periumbilical pain, and the characteristic finding that symptoms are only relieved by hot bathing or showering.

The syndrome occurs in habitual daily cannabis users and often leads to extensive and unnecessary medical testing before diagnosis, as the symptoms mimic many gastrointestinal conditions. Definitive resolution comes only with cessation of cannabis use.

The authors emphasize that with wider legalization and increasing availability, cannabis-related emergency department visits are rising, and healthcare providers need to recognize CHS early to avoid prolonged diagnostic workups.

Why it matters

CHS represents one of the clearest adverse effects of chronic heavy cannabis use. Its distinctive feature of hot water relief is nearly pathognomonic (uniquely characteristic of the condition), but many clinicians remain unaware of it, leading to repeated emergency visits, unnecessary imaging, endoscopies, and prolonged patient suffering before diagnosis.

The numbers in context

Cannabis-related ED visits are increasing with legalization. CHS features three phases: prodromal (early morning nausea), hyperemetic (intense vomiting), and recovery (after cessation).

How the study worked

Single case report with clinical description and literature context.

What this study cannot tell us

Single case report cannot establish prevalence, risk factors, or mechanisms. The pathophysiology of CHS remains incompletely understood. Why only some chronic heavy users develop the syndrome while others do not is unclear.

How to read the evidence

Preliminary evidence from a single case report. CHS is well-established in the broader literature but this study adds only one case.

When this study was published

Published in 2017. CHS awareness has grown significantly since.

The bigger picture

As cannabis use becomes more common, CHS has shifted from a medical curiosity to a routine emergency department presentation in many regions. Understanding this syndrome is important not because it affects all users, but because it affects a subset of heavy daily users and can cause significant morbidity and healthcare utilization if unrecognized.

Questions still open

What determines which heavy cannabis users develop CHS and which do not? Why does hot water relieve symptoms? Is there a threshold of use (frequency, quantity, potency) below which CHS does not occur?

Common questions

How common is cannabinoid hyperemesis syndrome?

The exact prevalence is unknown, but it appears to affect a subset of chronic, heavy daily cannabis users. As cannabis use has increased, CHS has become a more common emergency department presentation.

Why do hot showers help CHS?

The mechanism is not fully understood. One theory involves TRPV1 receptors (heat-sensitive receptors) in the gut that interact with the endocannabinoid system. Hot water may temporarily activate these receptors in a way that counteracts the nausea signals, but this remains speculative.

Read the original research

A patient with a curious case of cyclical vomiting.

JAAPA : official journal of the American Academy of Physician Assistants, 30(2), 1-3

View on PubMed ↗Publisher’s paper ↗

Citation

Phillips, Hayden R; Smith, David A. (2017). A patient with a curious case of cyclical vomiting.. JAAPA : official journal of the American Academy of Physician Assistants, 30(2), 1-3. https://doi.org/10.1097/01.JAA.0000511789.29560.74