Systematic review found medical cannabis may benefit some fibromyalgia patients with mild side effects

A systematic review of 10 studies (1,136 patients) found medical cannabis was generally safe and well-tolerated for fibromyalgia, with no serious adverse events reported.

Kurlyandchik, Inna et al.·Journal of alternative and complementary medicine (New York·2021·Moderate EvidenceSystematic Review
RTHC-03263Systematic ReviewModerate Evidence2021RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Systematic Review
Evidence
Moderate Evidence
Sample
N=945

What This Study Found

Across 3 RCTs and 6 observational studies, cannabis showed potential benefit for fibromyalgia symptoms with side effects limited to feeling "high," dizziness, dry mouth, cough, red eyes, and drowsiness. No serious adverse events were reported. The review could not identify which specific cannabis type or formulation was most effective.

Key Numbers

181 citations screened, 10 included. 1,136 patients total. 3 RCTs, 6 observational, 1 comparison study. Study sizes: 9-383 patients (mean 114, median 36). Adverse events: mild only, no serious events.

How They Did This

Systematic review searching MEDLINE, Embase, CINAHL, AMED, Scopus, and Cochrane CENTRAL (2000-2020). 10 of 181 identified studies met inclusion criteria. Total of 1,136 patients across all studies (intervention n=945, control n=108, crossover n=83).

Why This Research Matters

Fibromyalgia remains poorly treated by conventional medicine. This review confirms that medical cannabis has a favorable safety profile in this population, which is important given that many fibromyalgia patients are already using cannabis without clinical guidance.

The Bigger Picture

The safety finding is arguably more important than the efficacy signal at this stage. For a chronic condition where patients are often desperate for relief, knowing that medical cannabis has mild and manageable side effects allows for more informed shared decision-making.

What This Study Doesn't Tell Us

Only 10 studies, mostly observational. Heterogeneous study designs. Small sample sizes. Cannot determine optimal cannabis type, dose, or duration. Three different study designs limit synthesis.

Questions This Raises

  • ?Which cannabis formulation is most effective for fibromyalgia?
  • ?What is the optimal dosing strategy?
  • ?How does cannabis compare head-to-head with approved fibromyalgia drugs?

Trust & Context

Key Stat:
No serious adverse events across 1,136 patients in 10 studies
Evidence Grade:
Systematic methodology but limited by few studies, small samples, and heterogeneous designs.
Study Age:
2021 systematic review covering studies from 2000-2020.
Original Title:
Safety and Efficacy of Medicinal Cannabis in the Treatment of Fibromyalgia: A Systematic Review.
Published In:
Journal of alternative and complementary medicine (New York, N.Y.), 27(3), 198-213 (2021)
Database ID:
RTHC-03263

Evidence Hierarchy

Meta-Analysis / Systematic ReviewCombines many studies into one answer
This study
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / Observational
Case Report / Animal Study

Analyzes all available research on a topic using a structured method.

What do these levels mean? →

Frequently Asked Questions

Is medical cannabis safe for fibromyalgia?

Based on this review, medical cannabis appears safe with only mild side effects (dizziness, dry mouth, drowsiness). No serious adverse events were reported across 1,136 patients in 10 studies.

Does cannabis cure fibromyalgia?

No. The review found cannabis may help manage symptoms but could not establish definitive efficacy. More research is needed on which types and doses work best.

Read More on RethinkTHC

Cite This Study

RTHC-03263·https://rethinkthc.com/research/RTHC-03263

APA

Kurlyandchik, Inna; Tiralongo, Evelin; Schloss, Janet. (2021). Safety and Efficacy of Medicinal Cannabis in the Treatment of Fibromyalgia: A Systematic Review.. Journal of alternative and complementary medicine (New York, N.Y.), 27(3), 198-213. https://doi.org/10.1089/acm.2020.0331

MLA

Kurlyandchik, Inna, et al. "Safety and Efficacy of Medicinal Cannabis in the Treatment of Fibromyalgia: A Systematic Review.." Journal of alternative and complementary medicine (New York, 2021. https://doi.org/10.1089/acm.2020.0331

RethinkTHC

RethinkTHC Research Database. "Safety and Efficacy of Medicinal Cannabis in the Treatment o..." RTHC-03263. Retrieved from https://rethinkthc.com/research/kurlyandchik-2021-safety-and-efficacy-of

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.