Dronabinol reduced opioid withdrawal severity but didn't improve naltrexone treatment retention | Research

The takeaway

A synthetic THC pill (dronabinol) reduced opioid withdrawal symptoms during detox, but did not increase rates of completing naltrexone treatment for opioid dependence.

Read this if you're interested in how cannabinoids interact with opioid withdrawal and recovery.

Dronabinol reduced withdrawal severity (p=0.006) but not treatment retention

What the researchers found

Sixty opioid-dependent participants were randomized to receive dronabinol (30mg/day) or placebo during inpatient detoxification and transition to extended-release naltrexone. Dronabinol significantly reduced the severity of opioid withdrawal symptoms during the inpatient phase.

However, successful induction onto naltrexone (66% dronabinol vs. 55% placebo) and 8-week treatment completion rates (35% in both groups) were not significantly different. A post hoc finding revealed that 32% of participants who smoked marijuana during the outpatient phase, regardless of their assigned group, had lower insomnia and anxiety and were more likely to complete the full 8-week trial.

The study suggests dronabinol has a role in acute withdrawal management but may not be sufficient to improve longer-term treatment retention.

Why it matters

Opioid withdrawal is a major barrier to starting and maintaining treatment. Finding medications that ease this transition could save lives. While dronabinol helped with acute withdrawal, the treatment retention challenge remains unsolved.

The numbers in context

60 participants (40 dronabinol, 20 placebo). Dronabinol reduced withdrawal severity (p=0.006). Naltrexone induction: 66% dronabinol vs. 55% placebo (not significant). 8-week completion: 35% in both groups. 32% who smoked marijuana outpatient were more likely to complete treatment.

How the study worked

Randomized, double-blind, placebo-controlled trial. 40 participants received dronabinol 30mg/day and 20 received placebo during inpatient detoxification and naltrexone induction. All received extended-release naltrexone injections. Dronabinol or placebo continued for 5 weeks outpatient.

What this study cannot tell us

Unequal group sizes (2:1 randomization). The post hoc marijuana use finding was not pre-planned and should be interpreted cautiously. Sample size may have been insufficient to detect moderate differences in retention. Outpatient marijuana use was self-selected, introducing selection bias.

How to read the evidence

Randomized, double-blind, placebo-controlled trial with moderate sample size. Primary withdrawal outcome was positive; retention outcomes were null.

When this study was published

Published in 2015. Research on cannabinoids in opioid treatment continues.

The bigger picture

The endocannabinoid system interacts with the opioid system in ways that may help manage withdrawal. This study adds to evidence that cannabinoids could play a supportive role in opioid treatment, even if they are not a standalone solution for treatment retention.

Questions still open

Could higher or different dosing of dronabinol improve treatment retention? Does the post hoc finding about marijuana use during opioid treatment warrant a dedicated clinical trial? Would CBD be effective for opioid withdrawal without psychoactive effects?

Common questions

Can THC help with opioid withdrawal?

In this study, synthetic THC (dronabinol) significantly reduced the severity of opioid withdrawal symptoms during detoxification. However, it did not increase the likelihood of completing a full course of naltrexone treatment.

Does marijuana use help people stay in opioid treatment?

A post hoc finding suggested participants who used marijuana during the outpatient phase had lower anxiety and insomnia and were more likely to complete treatment, but this was not a pre-planned comparison and needs dedicated study.

Read the original research

The effects of dronabinol during detoxification and the initiation of treatment with extended release naltrexone.

Drug and alcohol dependence, 154, 38-45

View on PubMed ↗Publisher’s paper ↗

Citation

Bisaga, Adam; Sullivan, Maria A; Glass, Andrew; Mishlen, Kaitlyn; Pavlicova, Martina; Haney, Margaret; Raby, Wilfrid N; Levin, Frances R; Carpenter, Kenneth M; Mariani, John J; Nunes, Edward V. (2015). The effects of dronabinol during detoxification and the initiation of treatment with extended release naltrexone.. Drug and alcohol dependence, 154, 38-45. https://doi.org/10.1016/j.drugalcdep.2015.05.013