A clinical trial published yesterday found that a marijuana oil containing equal amounts of delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) was well tolerated and may help reduce pain, improve sleep and lessen the overall impact of fibromyalgia.
The study, published in Pain Research and Management, was conducted by researchers from Southern Cross University, Griffith University and Gold Coast University Hospital.
The double-blind, randomized, placebo-controlled trial included 24 adults with fibromyalgia. Participants were assigned to receive either a 1:1 THC:CBD marijuana oil or a placebo. The active oil contained 10 milligrams per milliliter each of THC and CBD.
Participants completed a four-week dose-titration period, followed by 12 weeks of stable dosing. The study was primarily designed to evaluate whether a larger trial would be feasible and whether the treatment appeared safe and tolerable, with symptom improvement measured as a secondary outcome.
Researchers found strong retention and adherence, with 22 of 24 participants completing the trial and all participants taking at least 90% of their doses. No serious adverse events were reported, and most side effects were mild. The most common adverse events in the treatment group included somnolence, dizziness, fatigue, nausea and dry mouth.
Although the study was small, results favored the marijuana oil group across several key measures. At both the post-titration point and Week 12, 70% of participants receiving THC:CBD oil reported at least a 30% reduction in pain. In comparison, 20% of placebo participants reported that level of pain reduction after titration, rising to 40% at Week 12.
Researchers also reported improvements in sleep quality and fibromyalgia impact among participants receiving the THC:CBD oil. A clinically meaningful improvement in fibromyalgia impact scores occurred in 40% of the marijuana oil group, compared with 10% of those receiving placebo.
The treatment group also saw improvements in several quality-of-life measures, including bodily pain and social functioning. Fatigue, anxiety and depression did not show clear significant improvements.
The authors cautioned that the findings should be interpreted carefully because of the small sample size, wide confidence intervals and the fact that all participants were female. Recruitment also fell short of the planned 36 participants, largely because of geographic barriers and legal concerns around THC and driving laws in Australia.
Researchers conclude by saying:
This randomised, double-blind, placebo-controlled feasibility study of 1:1 THC:CBD (10 mg/mL each) cannabis oil in fibromyalgia showed high retention and adherence, while recruitment fell short of targets under the study’s constraints. The intervention appeared well tolerated with no serious AEs in this small sample. Secondary outcomes suggest potential benefits in pain, sleep, function and quality of life, though findings should be interpreted cautiously given the small sample and wide confidence intervals. Larger, adequately powered trials with strategies to address recruitment barriers are needed to confirm efficacy and refine dosing.
Sponsored
