Cochrane Review Found No Convincing Evidence That Cannabinoids Help Fibromyalgia
A Cochrane systematic review found only two small studies (72 total participants) testing cannabinoids for fibromyalgia, with very low quality evidence and no convincing support for their use.
Quick Facts
What This Study Found
The Cochrane Collaboration, considered the gold standard for medical evidence review, found only two randomized controlled trials testing cannabinoids for fibromyalgia, with a combined total of just 72 participants. Both studies tested nabilone (a synthetic cannabinoid) at 1 mg/day.
No study reported the proportion of participants achieving meaningful pain relief (30% or 50% reduction) or significant improvement. All evidence was rated as very low quality due to indirectness, imprecision, and potential reporting bias.
Third-tier (very low quality) evidence suggested nabilone might be slightly better than placebo for pain and quality of life, and slightly better than amitriptyline for sleep. But the differences were modest and the evidence was insufficient for any clinical recommendation.
No studies were found testing herbal cannabis, plant-based cannabinoids, or any synthetic cannabinoid other than nabilone for fibromyalgia.
Key Numbers
2 RCTs included. 72 total participants (studies of 32 and 40). Both tested nabilone 1 mg/day at bedtime. Study durations: 4 and 6 weeks. Very low quality evidence overall. No studies of herbal cannabis or other cannabinoids found.
How They Did This
Cochrane systematic review searching CENTRAL, MEDLINE, and EMBASE through April 2016, plus clinical trial registries and author contact. Included RCTs of at least 4 weeks using any cannabis formulation for adults with fibromyalgia. Used three-tier evidence hierarchy and GRADE assessment.
Why This Research Matters
Fibromyalgia patients are among the most common medical cannabis users, yet this Cochrane review reveals that the evidence supporting this use is almost nonexistent. Only 72 total patients have been studied in controlled trials, and the evidence quality is very low. This represents a massive gap between patient behavior and scientific evidence.
The Bigger Picture
Cannabis is widely used for fibromyalgia based on patient reports, theoretical rationale (endocannabinoid deficiency hypothesis), and limited observational data. But the randomized trial evidence is almost completely absent. This Cochrane review highlights the urgent need for well-designed clinical trials, given how many patients are already using cannabinoids for this condition.
What This Study Doesn't Tell Us
The review is limited by the scarcity of available trials rather than by its own methodology. Only two small studies existed. Both used nabilone specifically, which may not represent the effects of other cannabinoids or whole-plant cannabis. The short study durations (4-6 weeks) may not capture long-term effects.
Questions This Raises
- ?Why have so few clinical trials been conducted given the widespread use of cannabis for fibromyalgia?
- ?Would whole-plant cannabis or CBD-dominant products show different results than nabilone?
- ?Does the endocannabinoid deficiency hypothesis support a stronger rationale for cannabinoids in fibromyalgia than the trial data currently shows?
Trust & Context
- Key Stat:
- Only 72 patients have been studied in RCTs of cannabinoids for fibromyalgia, with very low quality evidence.
- Evidence Grade:
- Moderate evidence assessment quality (Cochrane methodology is rigorous), but the underlying evidence it reviews is very low quality due to the scarcity and small size of available trials.
- Study Age:
- Published in 2016. Some additional studies of cannabinoids for fibromyalgia have since been conducted.
- Original Title:
- Cannabinoids for fibromyalgia.
- Published In:
- The Cochrane database of systematic reviews, 7(7), CD011694 (2016)
- Authors:
- Walitt, Brian, Klose, Petra(3), Fitzcharles, Mary-Ann(14), Phillips, Tudor, Häuser, Winfried
- Database ID:
- RTHC-01292
Evidence Hierarchy
Analyzes all available research on a topic using a structured method.
What do these levels mean? →Frequently Asked Questions
Does cannabis help fibromyalgia?
Many fibromyalgia patients report benefit, but as of this Cochrane review, only 72 patients had been studied in controlled trials, and the evidence was rated very low quality. There is currently no convincing clinical trial evidence supporting this use.
Why is the evidence so poor?
Very few randomized controlled trials have been conducted. Both existing studies tested only nabilone (a synthetic cannabinoid) in small groups for short periods. No studies of herbal cannabis or CBD products for fibromyalgia were found. The legal status of cannabis has historically made research difficult.
Read More on RethinkTHC
- CBD-oil-quality-guide
- anxiety-medication-after-quitting-weed
- cannabis-chemotherapy-nausea
- cannabis-chronic-pain-research
- cannabis-epilepsy-CBD-Epidiolex
- cbd-anxiety-research-evidence
- cbd-for-weed-withdrawal
- cbd-vs-thc-difference
- medical-benefits-of-cannabis
- quitting-weed-before-surgery
- quitting-weed-medication-interactions
- quitting-weed-pregnancy
- quitting-weed-pregnant
- seniors-older-adults-cannabis-risks-medications
- weed-breastfeeding-THC-breast-milk
Cite This Study
https://rethinkthc.com/research/RTHC-01292APA
Walitt, Brian; Klose, Petra; Fitzcharles, Mary-Ann; Phillips, Tudor; Häuser, Winfried. (2016). Cannabinoids for fibromyalgia.. The Cochrane database of systematic reviews, 7(7), CD011694. https://doi.org/10.1002/14651858.CD011694.pub2
MLA
Walitt, Brian, et al. "Cannabinoids for fibromyalgia.." The Cochrane database of systematic reviews, 2016. https://doi.org/10.1002/14651858.CD011694.pub2
RethinkTHC
RethinkTHC Research Database. "Cannabinoids for fibromyalgia." RTHC-01292. Retrieved from https://rethinkthc.com/research/walitt-2016-cannabinoids-for-fibromyalgia
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.