# Endocannabinoid System Research: Cannabis for Chronic Pain > **Author:** Benjamin Caplan, MD (ABFM Board Certified, MA Lic. #240562, NPI: 1962722637) > **Publisher:** CED Clinic (https://cedclinic.com) > **Canonical URL:** https://cedclinic.com/cannabinoids-chronic-pain-evidence-review-2025-2/ > **Published:** 2026-03-01T15:10:47-04:00 | **Last Modified / Clinically Audited:** 2026-09-28T11:13:13-04:00 > **Clinical Summary:** Explore the cannabinoids chronic pain evidence review 2025 showing modest pain relief and variable effects based on THC-to-CBD ratios and delivery methods. --- #### Clinical Takeaway Randomized controlled trial evidence through mid-2025 shows that cannabinoids provide measurable but modest pain relief for [chronic pain](https://cedclinic.com/cannabinoids-pain-management-opioid-alternative/) conditions, with effects varying based on THC-to-CBD ratio, cannabinoid source, and delivery method. The strength of that evidence remains limited, meaning clinicians should weigh potential benefits against known harms on an individual patient basis. No single cannabinoid formulation has emerged as a clear standard of care for [chronic pain management](https://cedclinic.com/cannabinoids-in-reward-processing-pain-perception/). ### #1 Cannabis-Based Products for Chronic Pain: An Updated Systematic Review. **Citation:** Chou Roger et al. *Cannabis-Based Products for [Chronic Pain](https://cedclinic.com/cannabinoids-pain-management-opioid-alternative/): An Updated Systematic Review.* Annals of internal medicine. 2026. PMID: 41429020. **Study type:** Journal Article, Systematic Review, Review  |  **Topic area:** Pain  |  **CED Score:** 16 Design: 5 Journal: 3 N: 4 Recency: 3 Pop: 2 Human: 1 Risk: -2 Why This Matters This updated systematic review addresses a critical evidence gap regarding cannabinoid efficacy and safety in [chronic pain management](https://cedclinic.com/cannabinoids-in-reward-processing-pain-perception/), where clinical guidance remains limited by heterogeneous trial data and unclear risk-benefit profiles. By synthesizing randomized controlled trials and applying rigorous bias assessment, this work provides clinicians with contemporary, high-quality evidence to inform prescribing decisions for a patient population with significant unmet analgesic needs. The stratification of cannabinoids by THC-to-CBD ratios offers practical pharmacological differentiation that may guide individualized treatment selection based on therapeutic targets and adverse effect tolerability. **Quality Gate Alerts:** - Preclinical only **Abstract:** BACKGROUND: Benefits and harms of cannabinoids for chronic pain are uncertain. PURPOSE: To update an evidence synthesis on cannabinoids for chronic pain. DATA SOURCES: Ovid MEDLINE, PsycINFO, Embase, the Cochrane Library, and Scopus to 28 July 2025. STUDY SELECTION: Randomized placebo-controlled trials. DATA EXTRACTION: Data extraction, risk of bias, and strength of evidence were dually reviewed. Cannabinoids were categorized by tetrahydrocannabinol (THC)-to-cannabidiol (CBD) ratio (high, comparable, or low), source (synthetic, purified, extracted), and administration method. DATA SYNTHESIS: 25 short-term (1 to 6 months) randomized controlled trials (n = 2303; 64% [neuropathic pain](https://cedclinic.com/cannabis-for-pain-relief/)) assessed cannabinoids. Oral synthetic/purified high THC-to-CBD (THC only) may slightly reduce and oromucosal, extracted, comparable THC-to-CBD ratio products probably slightly reduce pain severity (pooled differences, -0.78 and -0.54 points, respectively, [0 to 10 scale]), with moderate or large increased dizziness, sedation, and nausea. Among THC-only products, nabilone moderately reduced pain severity but dronabinol did not (pooled differences, -1.59 and -0.23 points, respectively). Low THC-to-CBD interventions may not improve outcomes. Although low THC-to-CBD mixed THC/CBD products may increase dizziness, sedation, and nausea, CBD alone may not increase harms. LIMITATION: Variability within categories; lack of product details; unclear U.S. availability of studied products; restricted to English-language studies. CONCLUSION: Comparable and high THC-to-CBD ratio cannabinoid products may result in small improvements in pain and increased common adverse events during short-term treatment of primarily [neuropathic pain](https://cedclinic.com/cannabis-for-pain-relief/); among high-ratio THC-only products, nabilone (but not dronabinol) reduced pain. Low THC-to-CBD products may not improve outcomes. Studies are needed on long-term outcomes and other cannabis product types. PRIMARY FUNDING SOURCE: Agency for Healthcare Research and Quality, U.S Clinical Perspective This updated systematic review provides a timely reassessment of cannabinoid efficacy for chronic pain, though clinicians should remain cautious about drawing firm conclusions given the heterogeneity of cannabis products, dosing regimens, and patient populations across trials. The authors’ stratification by THC-to-CBD ratios represents a methodologically sound attempt to parse differential effects, yet real-world [cannabis use](https://cedclinic.com/cannabis-cardiovascular-health-insights-2024/) rarely follows such neat pharmacological categorization, and individual patient response remains highly variable due to factors like baseline endocannabinoid tone, concurrent medications, and delivery methods that trials often cannot fully capture. Notably, many studies remain limited by small sample sizes, short follow-up periods, and the ongoing regulatory barriers that restrict high-quality research in this space, meaning our evidence base still lags behind clinical demand. Rather than viewing cannabinoids as a definitive solution, the practical implication is to consider them as a potential adjunctive tool for carefully selected patients with chronic pain who have exhausted or poorly tolerated conventional options, with [Full Article](https://doi.org/10.7326/ANNALS-25-03152)  |  [PubMed](https://pubmed.ncbi.nlm.nih.gov/41429020/) Further Reading CED Clinic Blog[Why Cannabis Works](https://cedclinic.com/why-cannabis-works/) Evidence Watch[Cannabis and Heart Health](https://cedclinic.com/cannabis-cardiovascular-health-study/) CED Clinic Blog[Cannabis for Sleep](https://cedclinic.com/cannabis-for-sleep/) [https://cedclinic.com/contact/](https://cedclinic.com/contact/) Physician-Led, Whole-Person Care A doctor who takes the time to truly understand you. Personal care that starts with listening and is guided by experience and ingenuity. Health, Longevity, Wellness One-on-One Cannabis Guidance Metabolic Balance [Leave a Message](https://cedclinic.com/contact/) [Metabolic Care](https://cedclinic.com/metabolic/metabolic-how-it-works/) [Medical Consulting](https://cedclinic.com/book/) [Cannabis Care](https://cedclinic.com/book/) [https://cedclinic.com/contact/](https://cedclinic.com/contact/) RELATED READING AT CED CLINIC Continue exploring the evidence [Cannabinoids Show Promise for Chronic Pain, But Evidence Remains Thin](https://cedclinic.com/cannabinoids-chronic-pain-evidence-review/) A detailed review of the current evidence on cannabinoids for chronic pain, highlighting benefits and limitations through 2025. [Read the full review](https://cedclinic.com/cannabinoids-chronic-pain-evidence-review/) [Endocannabinoid System & Chronic Pain: Clinical Evidence](https://cedclinic.com/cannabinoids-chronic-pain-clinical-evidence/) Explore clinical evidence linking the [endocannabinoid system](https://cedclinic.com/endocannabinoid-system-fear-extinction/) to chronic pain management and therapeutic potential. [Explore clinical evidence](https://cedclinic.com/cannabinoids-chronic-pain-clinical-evidence/) [Cannabis-Based Products for Chronic Pain: Clinical Evidence](https://cedclinic.com/cannabinoid-efficacy-chronic-pain-clinical-evidence/) An updated systematic review of cannabis-based products assessing efficacy and safety in chronic pain treatment. [View systematic review](https://cedclinic.com/cannabinoid-efficacy-chronic-pain-clinical-evidence/) Have thoughts on this? 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