Heavy cannabis use led to Wernicke's encephalopathy, a brain condition usually seen with alcoholism | Research

The takeaway

A 41-year-old heavy marijuana user developed Wernicke's encephalopathy (thiamine deficiency brain damage) after cannabis hyperemesis syndrome caused severe vomiting and malnutrition, a complication not typically associated with cannabis use.

Emergency physicians, neurologists, and clinicians treating cannabis hyperemesis syndrome.

Wernicke's from cannabis, not alcohol

What the researchers found

The patient presented with seizures secondary to cannabis hyperemesis-induced vomiting and hyponatremia. Brain MRI showed bilateral thalamic hyperintensities characteristic of Wernicke's encephalopathy. IV thiamine led to gradual improvement. The patient had no significant alcohol history (1-2 beers/week 20 years prior).

Why it matters

Wernicke's encephalopathy is traditionally associated with alcoholism. This case demonstrates that cannabis hyperemesis syndrome can cause sufficient malnutrition to produce this serious brain condition, a complication clinicians may not anticipate.

The numbers in context

41-year-old male. Status epilepticus at presentation. Bilateral thalamic hyperintensities on T2 FLAIR MRI. No significant alcohol history. Memory deficits and confabulations after stabilization. 2 months into rehabilitation at time of report.

How the study worked

Single case report with brain MRI documentation. Comprehensive negative workup for other causes (infectious, autoimmune). Clinical response to thiamine treatment supported the diagnosis.

What this study cannot tell us

Single case report. Remote alcohol history (though minimal) could theoretically have contributed. Cannabis hyperemesis syndrome leading to Wernicke's is presumably rare. Long-term cognitive outcome not reported.

How to read the evidence

Rated preliminary because this is a single case report, though it documents a novel and clinically important complication.

When this study was published

Published in 2019.

The bigger picture

Cannabis-induced hyperphagia creates an assumption that cannabis users are well-nourished. But cannabis hyperemesis reverses this, and the "munchies" diet tends to be nutritionally poor. Thiamine supplementation, routine in alcohol intoxication, may also be warranted for cannabis hyperemesis.

Questions still open

Should thiamine be routinely supplemented in cannabis hyperemesis cases? How common is subclinical thiamine deficiency among heavy cannabis users? Are other nutritional deficiencies prevalent in this population?

Common questions

What is Wernicke's encephalopathy?

A serious brain condition caused by severe thiamine (vitamin B1) deficiency, typically seen in alcoholics. It causes confusion, memory problems, and brain damage visible on MRI.

How did cannabis cause this?

Severe vomiting from cannabis hyperemesis syndrome, combined with nutritionally poor diet, led to thiamine deficiency severe enough to damage the brain. The authors suggest thiamine should be supplemented in cannabis intoxication cases.

Read the original research

Heavy Cannabis Use Associated with Wernicke's Encephalopathy.

Cureus, 11(7), e5109

View on PubMed ↗Publisher’s paper ↗

Citation

Chaudhari, Amit; Li, Zi Ying; Long, Alan; Afshinnik, Arash. (2019). Heavy Cannabis Use Associated with Wernicke's Encephalopathy.. Cureus, 11(7), e5109. https://doi.org/10.7759/cureus.5109