BACKGROUND::

Many cannabinoid medications are approved in North America or in Phase III trials, such as Dronabinol, Nabilone, or Nabiximols. Little is known about their subjective psychoactive effects when used for pain management. We hypothesized that when used for pain, dronabinol has psychoactive effects in a dose response relationship, whose peak effects are comparable to smoking marijuana.

METHODS::

With IRB approval and written consent, this was a randomized controlled trial of single dose placebo, 10 or 20 mg dronabinol in 30 chronic non-cancer pain patients taking opioids and not using marijuana. Hourly, for 8 hours during 3 monitored sessions, subjects completed the Addiction Research Center Inventory (ARCI). Comparison sample was the ARCI ratings in a study population with no pain (N=20), monitored every 30 minutes after smoking a 1.99% THC (low) and a 3.51% (high strength) marijuana cigarette.

RESULTS::

The 10 and 20 mg dronabinol doses had significantly elevated scores on 4/5 subscales vs. placebo over time (P<0.05). Average daily morphine use, total pain relief (TOTPAR), age, gender, and baseline pain level were not significant covariates. ARCI peak effects at 2 hours were similar to peak effects of smoked marijuana at 30 minutes (P=0.80, 10 mg=low, 20 mg=high strength).

CONCLUSIONS::

In pain patients, oral dronabinol has similar psychoactive effects to smoking marijuana. This risk must be considered in any decision to prescribe cannabinoid medications for pain.

PMID:

 

24281276

 

[PubMed – as supplied by publisher]