The Prescription Drug Nabilone Felt Like THC to Cannabis Users, Supporting Its Potential as a Quit-Aid | Research

The takeaway

In 6 cannabis users trained to identify THC, nabilone produced THC-like subjective effects and substituted for THC at doses of 1-5 mg, while methylphenidate (Ritalin) did not, supporting nabilone as a potential agonist replacement therapy.

Read this if you are interested in medication-assisted treatment for cannabis dependence.

Nabilone felt like THC to users; methylphenidate did not, supporting agonist replacement potential

What the researchers found

Six cannabis users learned to identify 25 mg oral THC under double-blind conditions. They were then tested with multiple doses of nabilone (a synthetic cannabinoid prescription drug), THC, and methylphenidate.

Nabilone shared discriminative-stimulus effects with THC: participants identified it as feeling like their training dose. It also produced comparable subjective effects and increased heart rate.

Methylphenidate (a dopamine stimulant) did not produce THC-like effects, serving as a negative control.

The authors noted that since agonist replacement therapy has been relatively successful for opioid (methadone), tobacco (nicotine replacement), and stimulant dependence, nabilone could potentially serve as a similar replacement therapy for cannabis use disorders.

Why it matters

No FDA-approved medication exists for cannabis dependence. If nabilone feels like THC to users, it could serve as a controlled substitute during treatment, similar to how methadone is used for opioid dependence.

The numbers in context

6 participants. Nabilone: 1, 2, 3, 5 mg tested. THC: 5, 10, 15, 25 mg. Methylphenidate: 5, 10, 20, 30 mg. Nabilone substituted for THC. Methylphenidate did not.

How the study worked

Double-blind drug discrimination study. Six cannabis users learned to discriminate 25 mg oral THC from placebo. Multiple doses of nabilone (1-5 mg), THC (5-25 mg), and methylphenidate (5-30 mg) were tested for THC substitution, subjective effects, and physiological measures.

What this study cannot tell us

Very small sample (6 participants). Drug discrimination measures subjective similarity, not treatment efficacy. Whether nabilone actually reduces cannabis use has not been tested in this study. The analogy to methadone may not hold for cannabis dependence.

How to read the evidence

Very small drug discrimination study (n=6). Demonstrates subjective similarity but not clinical efficacy for treating cannabis dependence.

When this study was published

Published in 2010. Nabilone has since been studied in small clinical trials for cannabis dependence with mixed but somewhat promising results.

The bigger picture

Agonist replacement (giving a controlled version of the same drug class) is the most successful pharmacological approach for several addictions. Extending this principle to cannabis dependence using nabilone could provide the first effective pharmacotherapy for this condition.

Questions still open

Would clinical trials confirm nabilone reduces cannabis use? At what dose does nabilone optimally substitute for cannabis? Could nabilone itself become a drug of abuse? Is partial agonist therapy (like buprenorphine for opioids) a better model?

Common questions

What is agonist replacement therapy?

It involves giving a controlled, pharmaceutical version of the same drug class to reduce craving and withdrawal while allowing supervised tapering. Methadone for heroin and nicotine patches for tobacco are successful examples. Nabilone could potentially fill this role for cannabis.

Is nabilone the same as THC?

Nabilone is a synthetic cannabinoid that activates CB1 receptors like THC. It is FDA-approved for chemotherapy-induced nausea. This study showed it feels similar to THC to experienced users, which is the first requirement for an effective agonist replacement therapy.

Read the original research

Substitution profile of the cannabinoid agonist nabilone in human subjects discriminating δ9-tetrahydrocannabinol.

Clinical neuropharmacology, 33(5), 235-42

View on PubMed ↗Publisher’s paper ↗

Citation

Lile, Joshua A; Kelly, Thomas H; Hays, Lon R. (2010). Substitution profile of the cannabinoid agonist nabilone in human subjects discriminating δ9-tetrahydrocannabinol.. Clinical neuropharmacology, 33(5), 235-42. https://doi.org/10.1097/WNF.0b013e3181e77428