Dronabinol did not help cannabis-dependent adults quit but did improve treatment retention and withdrawal symptoms

In 156 cannabis-dependent adults, dronabinol (synthetic THC) did not increase abstinence rates compared to placebo, but significantly improved treatment retention (77% vs 61%) and reduced withdrawal symptoms.

Levin, Frances R et al.·Drug and alcohol dependence·2011·Moderate EvidenceRandomized Controlled Trial
RTHC-00504Randomized Controlled TrialModerate Evidence2011RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Randomized Controlled Trial
Evidence
Moderate Evidence
Sample
N=156

What This Study Found

This was the first clinical trial testing an agonist substitution strategy for cannabis dependence, similar to how methadone is used for opioid dependence.

156 cannabis-dependent adults were randomized to dronabinol (20 mg twice daily) or placebo for 12 weeks, with all participants receiving weekly therapy. There was no significant difference in the primary outcome: 17.7% of dronabinol patients achieved 2 weeks of abstinence versus 15.6% on placebo.

However, dronabinol showed two significant secondary benefits. Treatment retention at the end of the maintenance phase was significantly higher with dronabinol (77%) compared to placebo (61%, p=0.02). Withdrawal symptoms were also significantly lower on dronabinol (p=0.02).

Both groups reduced marijuana use over time, but there were no between-group differences in overall reduction.

Key Numbers

156 participants. Abstinence: 17.7% dronabinol vs 15.6% placebo (not significant). Retention: 77% vs 61% (p=0.02). Withdrawal symptoms lower on dronabinol (p=0.02). Dose: 20 mg BID.

How They Did This

Randomized, double-blind, placebo-controlled, 12-week trial. 156 cannabis-dependent adults. 1-week placebo lead-in, then dronabinol 20 mg BID or placebo for 8 weeks maintenance, 2-week taper. Weekly motivational enhancement and relapse prevention therapy for all. Timeline followback for marijuana use assessment.

Why This Research Matters

While dronabinol did not increase abstinence, the improved retention and withdrawal management established proof of concept for agonist substitution in cannabis dependence, informing future medication development.

The Bigger Picture

The study opened the door for testing higher doses, combination medications, and more potent behavioral interventions alongside agonist substitution for cannabis dependence.

What This Study Doesn't Tell Us

Abstinence rates were low in both groups. Dronabinol dose may have been insufficient. Relapse often occurred during the taper/post-taper period. Self-reported marijuana use as primary outcome.

Questions This Raises

  • ?Would higher dronabinol doses produce better abstinence outcomes?
  • ?Could dronabinol be combined with other medications for additive effects?

Trust & Context

Key Stat:
77% retention on dronabinol vs 61% on placebo (p=0.02)
Evidence Grade:
Well-designed RCT with adequate sample size, though the primary outcome (abstinence) was not met.
Study Age:
Published in 2011. Cannabis dependence pharmacotherapy research has continued with combination strategies.
Original Title:
Dronabinol for the treatment of cannabis dependence: a randomized, double-blind, placebo-controlled trial.
Published In:
Drug and alcohol dependence, 116(1-3), 142-50 (2011)
Database ID:
RTHC-00504

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled TrialGold standard for testing treatments
This study
Cohort / Case-Control
Cross-Sectional / Observational
Case Report / Animal Study

Participants are randomly assigned to treatment or placebo groups to test cause and effect.

What do these levels mean? →

Frequently Asked Questions

Can medications help you quit cannabis?

Dronabinol (synthetic THC) did not significantly increase abstinence rates in this trial. However, it kept more people in treatment (77% vs 61%) and reduced withdrawal symptoms, suggesting medication-assisted approaches have potential but need refinement.

What is agonist substitution?

Similar to using methadone for heroin addiction, agonist substitution gives a controlled dose of a similar drug (dronabinol, which is synthetic THC) to manage withdrawal and cravings while the person works on behavior change.

Read More on RethinkTHC

Cite This Study

RTHC-00504·https://rethinkthc.com/research/RTHC-00504

APA

Levin, Frances R; Mariani, John J; Brooks, Daniel J; Pavlicova, Martina; Cheng, Wendy; Nunes, Edward V. (2011). Dronabinol for the treatment of cannabis dependence: a randomized, double-blind, placebo-controlled trial.. Drug and alcohol dependence, 116(1-3), 142-50. https://doi.org/10.1016/j.drugalcdep.2010.12.010

MLA

Levin, Frances R, et al. "Dronabinol for the treatment of cannabis dependence: a randomized, double-blind, placebo-controlled trial.." Drug and alcohol dependence, 2011. https://doi.org/10.1016/j.drugalcdep.2010.12.010

RethinkTHC

RethinkTHC Research Database. "Dronabinol for the treatment of cannabis dependence: a rando..." RTHC-00504. Retrieved from https://rethinkthc.com/research/levin-2011-dronabinol-for-the-treatment

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.