Cannabis and Cannabinoids for Chronic Pain: Evidence Review

How to read this page

This page summarizes research. It does not recommend cannabis, CBD or any cannabinoid for pain, and it gives no amounts for personal use. Evidence labels used here: approved medicine, promising but limited, mixed, insufficient evidence, no good evidence of benefit and evidence of harm. A "systematic review" pools every trial found on one question. A "meta-analysis" adds the numbers together. Where we looked and found nothing usable, the page says "Proper evidence not found".

Do not stop or change prescribed pain medicines because of anything here. New, severe or sudden pain needs medical care, not a research summary.

The short answer

Chronic pain overall

The largest recent review is a 2021 BMJ meta-analysis of 32 trials with 5,174 adults. Compared with placebo, non-inhaled medical cannabis or cannabinoids gave a small to very small improvement in pain relief, physical functioning and sleep quality. [1] Almost all trials used oral products (two used skin products), and follow-up lasted 1 to 5.5 months, so long-term effects are unknown. [1]

Other reviews fit that picture:

• A 2018 review summarized by NCCIH (47 studies) found 29% of people on cannabis or cannabinoids had a 30% pain reduction versus 26% on placebo, a gap that may be too small to matter to patients. [5]
• A 2015 JAMA review found moderate-quality evidence for chronic pain and spasticity, with more short-term side effects. [6]
• A 2022 review that sorted trials by medicine found moderate evidence for nabiximols and dronabinol in chronic pain; other pain effects had low, very low or no grade of evidence. [7]
• A 2026 JAMA review says trial evidence does not support cannabis or cannabinoids for most conditions they are promoted for, such as acute pain and insomnia. [8]

Nerve pain

A Cochrane review of 16 studies (1,750 people) found 39% of people on cannabis-based medicines had at least 30% pain relief versus 33% on placebo. [2] Nervous system side effects were reported by 61% versus 29%, and psychiatric side effects by 17% versus 5%. [2] The authors concluded the potential benefits may be outweighed by the harms. [2] A 2025 review of 22 trials found 15 reported pain reductions and 7 did not, and warned that small, short trials, high placebo response and unblinding from psychoactive effects make the results hard to interpret. [9]

Cancer pain

A 2023 Cochrane review of 14 studies (1,823 people) found moderate-certainty evidence that nabiximols (a THC and CBD mouth spray) and THC did not relieve moderate or severe cancer pain that persisted despite opioids. [3] Low-certainty evidence suggested CBD oil added nothing to specialist palliative care, and no studies used herbal cannabis. [3]

Joint pain and other pain types

The only rheumatoid arthritis review we read (2026) found three eligible studies: one randomized trial of 58 people on nabiximols and two observational studies at serious risk of bias. It judged the evidence insufficient. [4] For osteoarthritis, fibromyalgia and migraine, Proper evidence not found in the sources we read. For non-drug options, see acupuncture for knee osteoarthritis, acupuncture for back and neck pain and massage evidence by goal. Cannabinoids for MS-related pain are covered in multiple sclerosis symptoms.

What guidelines say

England's NICE advises against offering nabilone, dronabinol, THC, or CBD combined with THC for chronic pain in adults, and against CBD for chronic pain outside a clinical trial. [10] The NHS says the evidence is not yet strong enough to recommend medical cannabis for pain relief. [11] Those pages date from 2021 and 2022, so ask a clinician what applies now.

Store products are not the trial products

The trials above tested medicines and defined preparations. The FDA says unapproved CBD products have not been evaluated for whether they work, what dosage is right, or how they interact with other drugs. [12] In a US sample of 202 CBD products, 74% differed from their labeled CBD amount by at least 10%. [13] A review of skin-applied CBD found only eight trials, with high risk of bias. [14] See CBD quality and certificates of analysis.

Risks to weigh

In the BMJ review, oral medical cannabis probably caused a small increase in short-lived cognitive impairment, drowsiness, nausea and vomiting, and dizziness was clearly more common. [1] The FDA lists liver injury, drug interactions, drowsiness and mood changes as CBD risks, and warns that CBD with alcohol or other sedating drugs raises sedation. [15] Read cannabis adverse effects and use disorder, CBD medication interactions and impairment and driving. Laws differ by country and change; this is not legal advice.