Evidence Hub

Suspected Cannabinoid Hyperemesis Syndrome in a Traveler from a Cannabis-Legal Country: A Case Report from Japan

Tsuge S, Sakurai R, Kondo K, Kadota K, Hiki M, Watanabe S, Kondo Y

Juntendo medical journal, 2026

Abstract

Cannabinoid hyperemesis syndrome (CHS) is characterized by recurrent nausea, vomiting, and abdominal pain in chronic cannabis users. We report a case of suspected CHS in a 37-year-old Canadian male who presented to a Japanese emergency department (ED) with severe abdominal pain and persistent vomiting. He reported chronic cannabis use two to four times per week for several years, with the last use the day before departure from Canada. Urine drug screening was positive for tetrahydrocannabinol. Although the clinical presentation was consistent with the hyperemetic phase of CHS, a definitive diagnosis could not be established due to the single-visit nature of the encounter and incomplete acquisition of key diagnostic information. This case highlights the diagnostic challenges of CHS in foreign travelers presenting to EDs in cannabis-prohibited countries, where linguistic, cultural, and legal barriers may impede timely recognition. Early consideration of CHS and systematic history-taking are essential to avoid diagnostic delays in this population.

How strong is the evidence?

Evidence Hub reads this as a case report, done in people. Its evidence level is 5 of 5 (Very low · case / narrative / animal / in vitro / in silico). Case reports, narrative reviews, and animal, cell or computer-model studies give the weakest evidence for human health.

How the five levels of evidence work. The level is assigned automatically from the abstract and can be wrong, so check the paper.

Read the paper

Related studies

Go deeper in Evidence Hub

Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.

Open this study Sign up free