Cannabis and Cannabinoids for Pain and Sleep: Research Summary

How to read this page

This page summarizes research and does not recommend using cannabis or CBD for pain or sleep. Evidence labels used: promising but limited, mixed, insufficient evidence and evidence of harm. A "systematic review" combines all the trials found on a question. Trial amounts are not given here because they are not advice.

Pain Research

Small benefit for chronic pain: promising but limited. The largest recent review is a 2021 BMJ meta-analysis of 32 trials with 5,174 adults. For non-inhaled medical cannabis or cannabinoids, it found a small to very small improvement in pain relief, physical function and sleep quality compared with placebo. [1] Most trials used oral products (two used topical), and follow-up ranged from 1 to 5.5 months. [1]

The same review counted side effects. Oral medical cannabis probably caused a small increased risk of transient cognitive impairment, and dizziness was more common, especially in longer trials. [1]

Other reviews fit that picture:

• NCCIH summary (2019). A 2018 review of 47 studies found 29% of people taking cannabis or cannabinoids had a 30% reduction in pain versus 26% on placebo, a difference that may be too small to matter to patients. [2]
• JAMA review (2015). Moderate-quality evidence supported cannabinoids for chronic pain and spasticity, with more short-term adverse events. [3]
• Product-specific review (2022). Moderate evidence for nabiximols and for dronabinol in chronic pain, while all other significant effects had low, very low or no grade of evidence. [4]

What guidelines say. England's NICE advises against offering nabilone, dronabinol, THC, or CBD combined with THC for chronic pain in adults, and not to offer CBD for chronic pain outside a clinical trial. [5] The NHS says the evidence is not yet strong enough to recommend medical cannabis for pain relief. [6] These pages date from 2019 and 2022, so ask your clinician for current advice.

CBD products from stores. The trials in these reviews were of medicines and preparations; they do not tell you what a bottle or gummy from a shop would do. Labels on store products frequently miss the mark; in a US sample, 74% deviated from the labeled CBD amount by at least 10%. [7]

Other pain topics. Proper evidence not found in the reviews we read for cannabis in migraine, fibromyalgia or arthritis specifically. A single trial of skin-applied hemp seed oil on knee osteoarthritis is discussed in hemp foods and hemp seed oil. For non-drug options, see acupuncture for back and neck pain or massage evidence by goal.

Sleep Research

Insomnia: insufficient evidence. A 2026 Cochrane review of 9 trials (537 adults) found that, compared with placebo, medical cannabis may have little to no clinically meaningful effect on quality of sleep or satisfaction with sleep. [8] The certainty of that evidence was very low, and adverse events may be slightly more common with medical cannabis. [8]

A different review points the other way. A 2025 meta-analysis of six trials (1,077 people) found cannabinoids significantly improved sleep quality versus placebo, but the studies disagreed widely (heterogeneity of 88%), and CBD-only treatments showed no significant effect. [9] It included people with or without insomnia or poor sleep, which differs from the Cochrane review's focus on adults with insomnia. [9][8]

Earlier reviews were cautious:

• A 2020 review of insomnia disorder included five studies and judged all of poor quality, saying the results do not reliably inform evidence-based practice. [10]
• A 2023 review of CBD for insomnia stated that research supporting its effectiveness is inadequate. [11]
• NCCIH notes that better sleep in people with other illnesses may reflect improvement in the illness rather than a direct sleep effect, and that effects in people without other illnesses are uncertain. [2]

Label: insufficient evidence for cannabis and CBD as sleep treatments; mixed for THC-containing products, since some analyses favor them.

Risks to weigh

Sleepiness is a known effect of CBD, and the FDA warns that combining CBD with alcohol or other drugs that slow brain activity increases sedation and drowsiness, which can lead to injuries. [12] NIDA lists withdrawal insomnia among cannabis withdrawal symptoms. [13] CBD may also raise liver injury risk and change how medicines work. [12]

See cannabis adverse effects and use disorder and CBD. For sleep problems, the insomnia guide and CBT for insomnia explain other approaches, and sleep supplements and natural aids covers non-cannabis options.

If pain or poor sleep is affecting daily life, talk with a clinician. Do not stop prescribed pain or sleep medicines on your own.