Low-THC Medicinal Cannabis Did Not Work as a Substitute for Street Cannabis in Psychosis Patients | Research

The takeaway

A case series of seven inpatients with psychosis and treatment-resistant cannabis use disorder found that substituting street cannabis with a low-THC, high-CBD medicinal variant (Bedrolite) was not effective.

Psychiatrists, addiction specialists, harm reduction advocates.

Zero of seven inpatients successfully transitioned from street cannabis to low-THC medicinal cannabis as a harm reduction strategy.

What the researchers found

The low-THC medicinal cannabis variant Bedrolite was not effective in treating inpatients with psychotic disorders and comorbid cannabis use disorder. The harm reduction strategy of replacing high-THC street cannabis with low-THC medicinal cannabis did not achieve its goals.

Why it matters

With no proven treatments for cannabis use disorder in psychosis patients, harm reduction through cannabis substitution was a creative approach. Its failure here suggests that patients may be seeking the THC effects specifically, not just the cannabis experience.

The numbers in context

Seven inpatients studied. Bedrolite contains relatively low THC and relatively high CBD compared to typical street cannabis.

How the study worked

Case series of seven inpatients diagnosed with a psychotic disorder and treatment-resistant cannabis use disorder who received Bedrolite (low THC, relatively high CBD) as substitution therapy.

What this study cannot tell us

Very small case series (n=7). Inpatient setting may not reflect real-world use. Only one medicinal cannabis product tested. No control group for comparison.

How to read the evidence

Preliminary - small case series (n=7) with no control group, but informative as a negative result.

When this study was published

Published in 2018.

The bigger picture

This negative result is informative: it suggests that simply reducing THC content is not sufficient to address cannabis use disorder in psychosis. Other approaches like behavioral interventions or pharmacotherapy may be needed.

Questions still open

Would a product with moderate THC and high CBD work better? Are patients primarily seeking THC's psychoactive effects? Could gradual THC tapering through different cannabis strains be more effective?

Common questions

Can low-THC cannabis replace regular cannabis for people with psychosis?

This case series suggests not. Seven psychosis inpatients did not successfully switch from street cannabis to a low-THC, high-CBD medicinal product (Bedrolite), indicating patients may be seeking THC's specific effects.

What is Bedrolite?

Bedrolite is a standardized medicinal cannabis variety with relatively low THC and relatively high CBD. It was tested as a potential harm reduction substitute for high-THC street cannabis in psychosis patients.

Read the original research

Medicinal cannabis (Bedrolite) substitution therapy in inpatients with a psychotic disorder and a comorbid cannabis use disorder: A case series.

Journal of psychopharmacology (Oxford, England), 32(3), 353-356

View on PubMed ↗Publisher’s paper ↗

Citation

Schipper, Regi; Dekker, Mathilde; de Haan, Lieuwe; van den Brink, Wim. (2018). Medicinal cannabis (Bedrolite) substitution therapy in inpatients with a psychotic disorder and a comorbid cannabis use disorder: A case series.. Journal of psychopharmacology (Oxford, England), 32(3), 353-356. https://doi.org/10.1177/0269881117735684