A chronic vomiter previously diagnosed with cyclic vomiting syndrome actually had cannabinoid hyperemesis | Research

The takeaway

A patient with extensive prior workup for chronic vomiting and a previous diagnosis of cyclic vomiting syndrome was found to have cannabinoid hyperemesis syndrome, with symptoms resolving upon cannabis cessation.

Read this if you experience chronic unexplained nausea and vomiting and use cannabis regularly.

Patient misdiagnosed with cyclic vomiting syndrome for years actually had CHS

What the researchers found

A patient with a long history of nausea and vomiting had previously undergone extensive diagnostic workup and received a diagnosis of cyclic vomiting syndrome. Upon closer evaluation, the patient was found to have characteristic features of cannabinoid hyperemesis syndrome (CHS), including the classic association with chronic cannabis use and compulsive hot bathing behavior.

The case highlighted how CHS can be misdiagnosed as cyclic vomiting syndrome, leading to unnecessary and expensive diagnostic investigations. The review portion discussed potential mechanisms for CHS pathogenesis.

Why it matters

The antiemetic (anti-nausea) properties of cannabis are well known, making the paradoxical development of severe vomiting counterintuitive. This case reinforced the importance of considering CHS in the differential diagnosis and asking about cannabis use in patients with unexplained cyclic vomiting.

The numbers in context

Cannabis lifetime use prevalence estimated at 42-46% in the U.S. One patient rediagnosed from cyclic vomiting syndrome to CHS.

How the study worked

Single case report of a patient with prior diagnosis of cyclic vomiting syndrome who was rediagnosed with CHS, accompanied by a review of published literature on CHS pathophysiology.

What this study cannot tell us

Single case report. CHS pathophysiology remained incompletely understood. The distinction between CHS and cyclic vomiting syndrome may not always be clear-cut.

How to read the evidence

Single case report with literature review. Illustrative but limited as individual experience.

When this study was published

Published in 2014.

The bigger picture

CHS and cyclic vomiting syndrome share many clinical features, making differential diagnosis challenging. The key distinguishing factor is cannabis use history. Given the high prevalence of cannabis use, CHS may account for a significant proportion of cases currently diagnosed as cyclic vomiting syndrome.

Questions still open

How many patients diagnosed with cyclic vomiting syndrome actually have CHS? What proportion of chronic cannabis users develop CHS? What are the specific mechanisms by which chronic cannabinoid exposure produces paradoxical hyperemesis?

Common questions

Can CHS be confused with other conditions?

Yes. This patient was previously diagnosed with cyclic vomiting syndrome after extensive workup. CHS was identified when cannabis use history was properly assessed. The two conditions share many features.

Why would cannabis cause vomiting if it is known as anti-nausea?

This paradox is the hallmark of CHS. While short-term cannabis use has antiemetic effects, chronic use can paradoxically trigger severe cyclic vomiting in some individuals. The exact mechanism is not fully understood.

Read the original research

Cannabinoid hyperemesis syndrome: a case report and review of pathophysiology.

Clinical medicine & research, 12(1-2), 65-7

View on PubMed ↗Publisher’s paper ↗

Citation

Iacopetti, Corina L; Packer, Clifford D. (2014). Cannabinoid hyperemesis syndrome: a case report and review of pathophysiology.. Clinical medicine & research, 12(1-2), 65-7. https://doi.org/10.3121/cmr.2013.1179