Very high urine THC levels above 100 ng/mL could help doctors diagnose cannabinoid hyperemesis syndrome faster | Research

The takeaway

In 15 adolescent/young adult patients with cannabinoid hyperemesis syndrome, 14 of 15 had urinary THC metabolite levels above 100 ng/mL, suggesting this threshold could serve as a diagnostic aid.

Emergency physicians, gastroenterologists, pediatricians evaluating young patients with intractable vomiting

14 of 15 CHS patients had urinary THC-COOH above 100 ng/mL

What the researchers found

14 of 15 CHS patients had urinary THC-COOH concentrations above 100 ng/mL, with 7 exceeding 500 ng/mL. The one exception had not used cannabis for 2 weeks. All had normal GI workups. All reported frequent cannabis use for at least 1 month and intractable vomiting for at least 2 weeks.

Why it matters

CHS can be difficult to diagnose, often leading to extensive and expensive workups. If urinary THC-COOH above 100 ng/mL proves to be a reliable biomarker, it could shorten the diagnostic process significantly.

The numbers in context

15 patients; average age 17.7; 14/15 had THC-COOH >100 ng/mL; 7 had >500 ng/mL; 12 reported weight loss; all had normal GI workups; p<0.0005 for association

How the study worked

Retrospective case series of 15 patients referred to a pediatric gastroenterology service for intractable vomiting, found to have CHS with urinary THC-COOH measured by gas chromatography mass spectrometry (January 2018 to April 2019).

What this study cannot tell us

Very small case series (15 patients), single center, no control group of heavy cannabis users without CHS, retrospective design, THC-COOH levels depend on timing of last use.

How to read the evidence

Small retrospective case series without controls from a single pediatric center

When this study was published

Published in 2021. CHS recognition and diagnostic approaches continue to evolve.

The bigger picture

As cannabis use increases among adolescents and young adults, CHS is becoming more common. A simple urine test threshold could prevent unnecessary endoscopies, imaging, and hospitalization.

Questions still open

Would this 100 ng/mL threshold hold up in a larger validation study? Do all heavy cannabis users have these levels, or only those with CHS? Could serial THC-COOH monitoring track CHS treatment progress?

Common questions

How is cannabinoid hyperemesis syndrome diagnosed?

Currently through clinical history and exclusion of other causes. This study suggests urinary THC-COOH levels above 100 ng/mL (measured by mass spectrometry) could serve as a diagnostic biomarker.

What level of cannabis use leads to CHS?

All 15 patients in this study were frequent cannabis users with urinary THC metabolite levels indicating significant chronic exposure. The high levels (most >100 ng/mL, nearly half >500 ng/mL) suggest heavy, regular use is typically involved.

Read the original research

Urinary Cannabis Metabolite Concentrations in Cannabis Hyperemesis Syndrome.

Journal of pediatric gastroenterology and nutrition, 73(4), 520-522

View on PubMed ↗Publisher’s paper ↗

Citation

Cordova, Jonathan; Biank, Vincent; Black, Elizabeth; Leikin, Jerrold. (2021). Urinary Cannabis Metabolite Concentrations in Cannabis Hyperemesis Syndrome.. Journal of pediatric gastroenterology and nutrition, 73(4), 520-522. https://doi.org/10.1097/MPG.0000000000003220