Patient's positive fentanyl tests traced to fentanyl-laced street cannabis | Research

The takeaway

A 50-year-old man in opioid addiction treatment kept testing positive for fentanyl despite abstaining from opioids. The source was traced to his street-purchased cannabis, and switching sources resolved the fentanyl-positive tests.

Addiction medicine providers, harm reduction advocates, and cannabis consumers who purchase from unregulated sources.

Fentanyl-positive tests resolved after changing cannabis source

What the researchers found

A patient receiving buprenorphine for opioid use disorder repeatedly tested positive for fentanyl on urine drug screens while denying opioid use but admitting to smoking street cannabis 2-3 times weekly. After changing cannabis sources, fentanyl tests became negative and remained so.

Why it matters

This case demonstrates that fentanyl contamination of street cannabis is a real phenomenon that can complicate addiction treatment and put cannabis users at risk of unintentional opioid exposure.

The numbers in context

Patient was 50 years old, using cannabis 2-3 times weekly for headache relief and sleep. Fentanyl-positive UDS resolved after changing cannabis source. Stable on buprenorphine afterward.

How the study worked

Single case report from an office-based opioid treatment program documenting the timeline of fentanyl-positive urine drug screens in relation to cannabis source changes.

What this study cannot tell us

Single case report with limited generalizability. No laboratory testing of the cannabis itself was performed. The frequency of fentanyl contamination in street cannabis is unknown.

How to read the evidence

Preliminary: single case report.

When this study was published

Published in 2020 in Journal of the American Pharmacists Association.

The bigger picture

As the fentanyl crisis intersects with the unregulated cannabis market, this case highlights the harm reduction argument for regulated cannabis sources that can be tested for contaminants.

Questions still open

How common is fentanyl contamination of street cannabis? Should addiction treatment programs consider cannabis adulteration when interpreting drug screens? Would legal cannabis access reduce this risk?

Common questions

Is fentanyl-laced cannabis common?

The case report notes that there is no systematic monitoring or reliable data on the frequency of cannabis adulteration with fentanyl. This case demonstrates it can occur, but how often is unknown.

Why would cannabis be laced with fentanyl?

The case does not determine why, and intentional lacing versus cross-contamination during handling is unclear. In unregulated drug markets, products can become contaminated at any point in the supply chain.

Read the original research

Unintentional use of fentanyl attributed to surreptitious cannabis adulteration.

Journal of the American Pharmacists Association : JAPhA, 60(6), e370-e374

View on PubMed ↗Publisher’s paper ↗

Citation

Hopwood, Taylor; Dowd-Green, Caitlin; Mason, Melissa; Stewart, Rosalyn W. (2020). Unintentional use of fentanyl attributed to surreptitious cannabis adulteration.. Journal of the American Pharmacists Association : JAPhA, 60(6), e370-e374. https://doi.org/10.1016/j.japh.2020.07.003