Cannabis hyperemesis patients had similar hair THC levels as recreational users without vomiting

Hair cannabinoid analysis found similar THC concentrations in people with cannabis hyperemesis syndrome and recreational users without symptoms, suggesting heavy use is necessary but not sufficient to trigger the condition.

Albert, Khala et al.·CJEM·2019·Preliminary EvidenceCase-Control
RTHC-01904Case ControlPreliminary Evidence2019RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Case-Control
Evidence
Preliminary Evidence
Sample
Not reported

What This Study Found

Hair cannabinoid concentrations were similar between cannabis hyperemesis patients (THC median 220 pg/mg), recreational user controls (150 pg/mg), and emergency department controls (270 pg/mg). The only significant difference was a 2.6-fold lower THC:CBN ratio in hyperemesis cases compared to recreational user controls.

Key Numbers

Hair THC: cases 220 pg/mg (median), recreational controls 150 pg/mg, ED controls 270 pg/mg. THC:CBN ratio was 2.6-fold lower in cases (95% CI 1.3-5.7). Hair CBD was often unquantifiably low in all groups. 46 total subjects analyzed.

How They Did This

Age- and sex-matched case-control study comparing hair cannabinoid concentrations (THC, CBN, CBD, THC-COOH) in 16 cannabis hyperemesis patients, 16 recreational user controls, and 14 emergency department controls. All subjects had positive urine THC.

Why This Research Matters

Cannabis hyperemesis syndrome remains poorly understood. This study suggests it is not simply caused by consuming more cannabis than others. Individual susceptibility likely plays a role, similar to motion sickness or morning sickness.

The Bigger Picture

If hyperemesis were purely dose-dependent, heavy users would show higher cannabinoid levels. They did not. This points toward idiosyncratic susceptibility, which could eventually lead to identifying who is at risk before symptoms develop.

What This Study Doesn't Tell Us

Small sample size (16 cases). Hair analysis reflects average exposure over months but cannot capture acute dosing patterns. The THC:CBN ratio finding needs replication. Specific cannabis products and consumption methods were not controlled.

Questions This Raises

  • ?What does the lower THC:CBN ratio in hyperemesis patients mean mechanistically?
  • ?Are there genetic factors that predispose certain heavy users to hyperemesis?
  • ?Could the THC:CBN ratio serve as a biomarker for risk?

Trust & Context

Key Stat:
220 vs 150 pg/mg (similar)
Evidence Grade:
Rated preliminary due to small sample size and the novel nature of using hair analysis for this condition.
Study Age:
Published in 2019. Cannabis hyperemesis syndrome continues to be an active area of emergency medicine research.
Original Title:
Hair cannabinoid concentrations in emergency patients with cannabis hyperemesis syndrome.
Published In:
CJEM, 21(4), 477-481 (2019)
Database ID:
RTHC-01904

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-ControlFollows or compares groups over time
This study
Cross-Sectional / Observational
Case Report / Animal Study

Compares people with a condition to similar people without it.

What do these levels mean? →

Frequently Asked Questions

What is cannabis hyperemesis syndrome?

A condition characterized by repeated episodes of severe vomiting in regular cannabis users. It is often relieved by hot showers and resolves with cannabis cessation.

Does using more cannabis cause hyperemesis?

Heavy use appears necessary, but this study found that hyperemesis patients did not have higher hair THC levels than heavy users without symptoms. Individual susceptibility likely plays a role.

What was different about the hyperemesis patients?

The only significant difference was a lower THC:CBN ratio in their hair, meaning they had relatively less THC compared to cannabinol. The significance of this finding is unclear.

Read More on RethinkTHC

Cite This Study

RTHC-01904·https://rethinkthc.com/research/RTHC-01904

APA

Albert, Khala; Sivilotti, Marco L A; Gareri, Joey; Day, Andrew; Ruberto, Aaron J; Hookey, Lawrence C. (2019). Hair cannabinoid concentrations in emergency patients with cannabis hyperemesis syndrome.. CJEM, 21(4), 477-481. https://doi.org/10.1017/cem.2018.479

MLA

Albert, Khala, et al. "Hair cannabinoid concentrations in emergency patients with cannabis hyperemesis syndrome.." CJEM, 2019. https://doi.org/10.1017/cem.2018.479

RethinkTHC

RethinkTHC Research Database. "Hair cannabinoid concentrations in emergency patients with c..." RTHC-01904. Retrieved from https://rethinkthc.com/research/albert-2019-hair-cannabinoid-concentrations-in

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.