CBD cigarettes reduced need for illegal high-THC cannabis in patient with schizophrenia | Research

The takeaway

A schizophrenia patient with cannabis and cocaine use disorders who had been hospitalized 30 times over 8 years reported significantly less need for illegal cannabis after switching to low-THC CBD cigarettes, with no hospitalizations since.

Psychiatrists treating dual diagnosis patients, harm reduction advocates, and anyone interested in CBD as a cannabis substitute.

30 hospitalizations before vs zero after CBD cigarette introduction

What the researchers found

After years of treatment failure with 30 hospitalizations, introducing CBD cigarettes (<1% THC) as adjunctive therapy, combined with off-label methylphenidate, led the patient to report significantly less need for illegal high-THC cannabis. He stopped cocaine use and had no further hospitalizations.

Why it matters

Patients with co-occurring schizophrenia and substance use disorders are among the hardest to treat. This case suggests CBD cigarettes may serve as a harm reduction substitute for high-THC cannabis in patients who are unable or unwilling to stop smoking cannabis entirely.

The numbers in context

30 hospitalizations over 8 years prior; CBD cigarettes <1% THC; no hospitalizations since intervention; cocaine use ceased

How the study worked

Single clinical case report of a male patient with schizophrenia, combined personality disorder, cannabis use disorder, and cocaine use disorder, treated with CBD cigarettes and methylphenidate after exhausting conventional treatment approaches over 8 years.

What this study cannot tell us

Single case report. Cannot attribute improvement solely to CBD cigarettes given concurrent methylphenidate. Placebo effect and therapeutic relationship may play a role. No long-term follow-up data provided.

How to read the evidence

Single case report with no controls, though the dramatic change from 30 hospitalizations to zero is clinically notable.

When this study was published

Published in 2021.

The bigger picture

Harm reduction approaches that accept some continued substance use while reducing the most harmful forms may be more practical than abstinence-only approaches for patients with treatment-resistant dual diagnoses.

Questions still open

Would CBD cigarettes show similar benefits in a controlled trial of schizophrenia patients with CUD? Is the benefit from CBD itself or from replacing high-THC cannabis with a low-THC alternative? How long do these improvements last?

Common questions

Did the patient stop using cannabis entirely?

No. The approach was harm reduction, not abstinence. The patient switched from illegal high-THC cannabis to legal CBD cigarettes with less than 1% THC, reporting significantly less need for the illegal product.

Was only CBD used?

No. The patient also received off-label methylphenidate alongside the CBD cigarettes, so the improvement cannot be attributed to CBD alone.

Read the original research

Case Report: CBD Cigarettes for Harm Reduction and Adjunctive Therapy in a Patient With Schizophrenia and Substance Use Disorder.

Frontiers in psychiatry, 12, 712110

View on PubMed ↗Publisher’s paper ↗

Citation

Meyer, Maximilian; Walter, Marc; Borgwardt, Stefan; Scheidegger, Alexandra; Lang, Elisabeth; Köck, Patrick. (2021). Case Report: CBD Cigarettes for Harm Reduction and Adjunctive Therapy in a Patient With Schizophrenia and Substance Use Disorder.. Frontiers in psychiatry, 12, 712110. https://doi.org/10.3389/fpsyt.2021.712110