Research Database
CBD
Cannabidiol

CBD Research

A non-psychoactive cannabinoid with wide-ranging therapeutic potential. CBD is FDA-approved for certain epilepsy conditions and studied for anxiety, inflammation, and pain.

Non-psychoactiveAnti-inflammatoryAnxiolyticAnticonvulsant
63studies
78,384participants
Browse PubMed
A
Evidence Grade
Strong Evidence

Based on 63 peer-reviewed studies in our database.

Outcome Distribution

37%
13%
11%
Positive
23 studies37%

Study found evidence of effectiveness

Mixed
5 studies8%

Results varied by condition or dose

Negative
8 studies13%

No significant effect found

Inconclusive
7 studies11%

More research needed

* Outcomes are based on our curated selection of research reviews. Individual study quality varies.

Study Types

Systematic Review (22)Randomized Controlled Trial (19)Meta-Analysis (12)Observational Study (8)Patient Survey (2)
Evidence:
AStrong
BModerate
CEmerging
DLimited

CBD Research Reviews

63 studies
A
Strong Evidence
2024
Meta-Analysis

Cannabis vs Opioids for Chronic Pain: Which Works Better?

Positive Results

In this landmark comparison of 90 trials with 22,028 patients, cannabis was found to be similarly effective to opioids for chronic pain relief, but with a critical advantage: patients on cannabis were 45% less likely to stop treatment due to adverse events compared to those on opioids.

22,028participants
|
BMJ Open
Chronic Pain
B
Moderate Evidence
2024
Randomized Controlled Trial

CBD for Sleep: What the Latest Clinical Trial Found

Mixed Results

In this rigorous 2024 trial, 150mg of nightly CBD was no better than placebo for most sleep measures in people with insomnia. While CBD users reported better well-being and showed slightly improved objective sleep efficiency, the primary sleep outcomes were not significantly different from placebo.

30participants
|
Journal of Clinical Sleep Medicine
Insomnia
B
Moderate Evidence
2024
Systematic Review

CBD for Chronic Pain: 2024 Systematic Review of the Evidence

Positive with Caveats

This 2024 systematic review of 15 studies found that most research shows 42-66% pain reduction with CBD or CBD+THC. However, 3 studies found no benefit, and the evidence overall is limited by small study numbers and varied methods.

|
Pain Management Nursing
Chronic Pain
A
Strong Evidence
2024
Systematic Review

Clinical Practice Guidelines: Cannabis for Chronic Pain & Co-Occurring Conditions (2024)

Positive Results

These 2024 clinical practice guidelines, based on 70 studies, conclude that cannabis-based medicines show "moderate benefit" for chronic pain and also help related conditions like sleep problems and anxiety. The guidelines provide practical dosing and titration recommendations for clinicians.

|
Cannabis and Cannabinoid Research
Chronic PainAnxiety+3
B
Moderate Evidence
2024
Randomized Controlled Trial

Cannabis and Your Heart: What THC vs CBD Do Differently

Positive with Caveats

THC significantly increases heart rate (~17 bpm), arterial stiffness, and reduces cardiac function—effects that could increase cardiovascular risk. CBD did NOT cause these cardiovascular effects. Smoking vs vaping THC made no difference.

22participants
|
Journal of the American Heart Association
A
Strong Evidence
2024
Meta-Analysis

Cannabinoids in Children: Safety Data from 23 Clinical Trials

Negative Results

Cannabinoids used for medical purposes in children and adolescents were associated with an increased risk of adverse events, including 3x higher withdrawal rates due to adverse events and nearly 2x higher serious adverse events compared to controls.

3,612participants
|
JAMA Pediatrics
EpilepsyNausea
A
Strong Evidence
2024
Systematic Review

ASCO Guidelines: Do Not Use Cannabis to Treat Cancer Itself

Negative Results

Clinicians should recommend against using cannabis or cannabinoids as a cancer-directed treatment unless within the context of a clinical trial. Cannabis may improve refractory chemotherapy-induced nausea and vomiting when added to standard antiemetics.

0
|
Journal of Clinical Oncology
CancerNausea+1
A
Strong Evidence
2023
Systematic Review

Cannabis Benefits and Risks: What 101 Studies Reveal

Positive with Caveats

This comprehensive umbrella review of 101 meta-analyses found high-certainty evidence that CBD effectively reduces seizures in epilepsy, and cannabis-based medicines help chronic pain (30% pain reduction), MS spasticity, and IBD—but also identified clear risks during pregnancy, for mental health, and while driving.

|
BMJ
Chronic PainEpilepsy+3
B
Moderate Evidence
2023
Systematic Review

Cannabis and Surgery: Guidelines for Patients

Positive with Caveats

These consensus guidelines from the American Society of Regional Anesthesia address managing surgical patients who use cannabis. Key points: cannabis users may need higher anesthetic doses, be at increased risk for negative outcomes, and should disclose use to surgical teams.

|
Regional Anesthesia and Pain Medicine
B
Moderate Evidence
2023
Systematic Review

Medical Cannabis for Chronic Pain: A Practical Review

Positive Results

This 2023 review of 77 articles concludes that medical cannabis provides adequate pain management for chronic nonmalignant pain. THC and CBD work through the endocannabinoid system to reduce pain perception and symptom frequency.

|
Current Pain and Headache Reports
Chronic PainMigraines+2
B
Moderate Evidence
2022
Systematic Review

Cannabis for Pain: A Complete Overview of the Evidence

Positive with Caveats

This scoping review found cannabis has been shown useful for both acute and chronic pain, with the strongest evidence for MS-related pain and as an adjunct in cancer pain. However, evidence is weak for neuropathic pain, rheumatic conditions, and headache, and there is no strong evidence for using cannabis to reduce opioid use.

|
Brazilian Journal of Anesthesiology
Chronic PainNeuropathy+2
A
Strong Evidence
2022
Systematic Review

Cannabis for MS Symptoms: The Cochrane Review

Positive with Caveats

This Cochrane review found that cannabis-based medicines may reduce spasticity and chronic pain in multiple sclerosis, but evidence quality is limited. Nabiximols (Sativex) shows the most evidence for MS spasticity, though side effects are common.

|
Cochrane Database of Systematic Reviews
Multiple Sclerosis
B
Moderate Evidence
2022
Observational Study

Cannabis Users Have More Pain After Surgery

Negative Results

Cannabis users had significantly worse outcomes after surgery: higher pain scores, higher opioid consumption, and more sleep disturbance than non-users. This suggests preoperative cannabis use is a risk factor for postoperative pain.

654participants
|
Journal of Obstetrics and Gynaecology Canada
Chronic Pain
C
Emerging Evidence
2022
Observational Study

Medical Cannabis for Autism: What We Know So Far

Positive with Caveats

CBD-rich medical cannabis appears to be an effective, tolerable, and relatively safe option for symptoms associated with autism spectrum disorder, including irritability and sleep problems. However, no placebo-controlled trials exist yet, and long-term safety is unknown.

|
Cannabis and Cannabinoid Research
Autism
A
Strong Evidence
2022
Randomized Controlled Trial

CBD for Arthritis Pain: A Controlled Trial Shows No Benefit

Negative Results

In this rigorous 12-week trial, CBD (20-30mg daily) showed NO benefit over placebo for hand osteoarthritis or psoriatic arthritis pain. Pain intensity, sleep, anxiety, depression, and function were all the same as placebo.

129participants
|
Pain
ArthritisChronic Pain
A
Strong Evidence
2021
Meta-Analysis

Does Cannabis Really Help Chronic Pain? What 32 Clinical Trials Found

Positive with Caveats

Analyzing 32 clinical trials with 5,174 patients, this BMJ meta-analysis found that medical cannabis provides a small but real improvement in chronic pain—about 10% more patients experience meaningful relief compared to placebo. Sleep quality also improved, though side effects like dizziness occur in some patients.

5,174participants
|
BMJ
Chronic PainCancer
B
Moderate Evidence
2021
Randomized Controlled Trial

Medicinal Cannabis for Insomnia: A Positive Trial

Positive Results

In this controlled trial, a medicinal cannabinoid extract significantly improved chronic insomnia—patients slept over an hour longer and fell asleep 8 minutes faster. Insomnia severity scores improved by 5 points, and patients reported better sleep quality and feeling more rested upon waking.

24participants
|
Sleep
Insomnia
A
Strong Evidence
2021
Systematic Review

Medical Cannabis and Driving: What Patients Must Know

Inconclusive

THC impairs driving performance and increases crash risk, with effects lasting 8 hours or more with oral products. Patients should avoid driving during treatment initiation and for several hours or more after each dose.

|
Australian Journal of General Practice
A
Strong Evidence
2021
Systematic Review

The Endocannabinoid System: Why Cannabis Works

Positive Results

The endocannabinoid system (ECS) regulates pain, mood, appetite, memory, and immune function. Because this system is involved in so many conditions—from chronic pain to neurological diseases—cannabis-based medicines have potential for treating diverse disorders.

|
International Journal of Molecular Sciences
Chronic PainAnxiety+1
B
Moderate Evidence
2021
Meta-Analysis

Cannabis for Cancer Wasting: The Evidence is Lacking

Negative Results

This meta-analysis of 5 RCTs with 934 patients found NO evidence that cannabis helps cachexia (cancer wasting syndrome). Appetite, weight, and quality of life did not improve compared to placebo. There is currently insufficient evidence to recommend cannabinoids for cachexia.

934participants
|
Cannabis and Cannabinoid Research
Cancer
B
Moderate Evidence
2021
Randomized Controlled Trial

First PTSD Cannabis Trial: No Treatment Outperformed Placebo

Negative Results

All treatment groups, including placebo, showed good tolerability and significant improvements in PTSD symptoms during three weeks of treatment, but no active treatment statistically outperformed placebo in this brief, preliminary trial.

80participants
|
PLoS One
PtsdAnxiety
B
Moderate Evidence
2020
Randomized Controlled Trial

THC Cannabis Oil for Fibromyalgia: A Controlled Trial

Positive Results

In this 8-week controlled trial, women with fibromyalgia taking THC-rich cannabis oil showed significantly improved quality of life scores compared to placebo. Pain, fatigue, ability to work, and overall well-being all improved—with no intolerable side effects.

17participants
|
Pain Medicine
Fibromyalgia
B
Moderate Evidence
2020
Meta-Analysis

Cannabinoids for Chronic Pain: Effect Sizes Are Small

Positive with Caveats

Pain intensity of chronic non-cancer patients was reduced by cannabinoids consumption, but effect sizes were small. Efficacy for neuropathic and non-neuropathic pain was similar.

0
|
Journal of Neuroimmune Pharmacology
Chronic PainNeuropathic Pain
B
Moderate Evidence
2020
Systematic Review

CBD Serious Side Effects: What the Clinical Trials Show

Mixed Results

Serious adverse effects related to CBD in RCTs are rare and include mainly elevated transaminases, convulsion, sedation, lethargy, and upper respiratory tract infections. These are related to drug-drug interactions with valproate and clobazam.

0
|
Expert Opinion on Drug Metabolism and Toxicology
EpilepsyChronic Pain
A
Strong Evidence
2019
Meta-Analysis

Can Cannabis Treat Mental Health Conditions? The Evidence

Inconclusive

This comprehensive Lancet Psychiatry analysis of 83 studies found scarce evidence that cannabis helps mental health conditions. The only modest benefit was for anxiety in people already using cannabis for other conditions like chronic pain—and even this evidence was very low quality.

3,067participants
|
Lancet Psychiatry
AnxietyDepression+1
B
Moderate Evidence
2019
Randomized Controlled Trial

THC vs CBD for Fibromyalgia: Comparing Cannabis Varieties

Positive with Caveats

This Dutch trial compared four cannabis varieties in fibromyalgia patients and found unexpected results: while balanced THC/CBD produced the most pain relief, adding CBD to THC actually reduced THC's pain-relieving effects. THC-containing varieties improved pressure pain tolerance, but effects were modest overall.

20participants
|
Pain
Fibromyalgia
B
Moderate Evidence
2019
Systematic Review

Cannabis: Both Benefits and Risks Explained

Mixed Results

Cannabis has both therapeutic potential and documented risks. While cannabinoids show promise for neurological and psychiatric conditions, repeated use is associated with respiratory, cardiovascular, cognitive, and psychiatric adverse effects. The evidence requires careful weighing of benefits against harms.

|
Clinical Pharmacology and Therapeutics
B
Moderate Evidence
2019
Patient Survey

Medical Cannabis for Cancer Patients: Real-World Results

Positive Results

Cancer patients in Minnesota's medical cannabis program showed significant improvement across ALL 8 symptoms tracked—anxiety, appetite, depression, sleep, fatigue, nausea, pain, and vomiting—within 4 months. Only 10.5% reported adverse effects.

|
Journal of Oncology Practice
CancerChronic Pain+4
B
Moderate Evidence
2019
Randomized Controlled Trial

Cannabis Spray Reduces Spasticity in ALS: First Positive Trial

Positive Results

Nabiximols had a positive effect on spasticity symptoms in patients with motor neuron disease and had an acceptable safety and tolerability profile. This is the first positive proof-of-concept trial for cannabinoids in ALS spasticity.

59participants
|
The Lancet Neurology
AlsSpasticity
B
Moderate Evidence
2018
Systematic Review

Cannabis for Nerve Pain: The Cochrane Review

Positive with Caveats

This Cochrane review of 16 studies found that cannabis-based medicines provide modest pain relief for neuropathic pain—about 1 in 11 patients achieve meaningful improvement. However, side effects are common, with nervous system and psychiatric effects occurring more frequently than with placebo.

1,750participants
|
Cochrane Database of Systematic Reviews
NeuropathyChronic Pain
A
Strong Evidence
2018
Meta-Analysis

Cannabis for Chronic Pain: A Critical Look at 104 Studies

Positive with Caveats

This rigorous meta-analysis of 104 studies found cannabis provides modest pain relief—about 1 in 24 patients benefit—but with a high side effect burden: 1 in 6 experience harm. The authors concluded it "seems unlikely that cannabinoids are highly effective medicines" for chronic pain.

9,958participants
|
Pain
Chronic PainNeuropathy+2
C
Emerging Evidence
2018
Systematic Review

Cannabis for Crohn's Disease: What the Research Shows

Inconclusive

The effects of cannabis and cannabis oil on Crohn's disease are uncertain. No firm conclusions regarding efficacy and safety can be drawn from the available evidence.

93participants
|
The Cochrane Database of Systematic Reviews
Crohns DiseaseIbd
A
Strong Evidence
2018
Systematic Review

What We Really Know About Medical Cannabis: A Review of Reviews

Mixed Results

There is reasonable evidence that cannabinoids improve nausea and vomiting after chemotherapy. They might improve spasticity. There is uncertainty about whether they improve pain, but if they do, it is neuropathic pain and the benefit is likely small. Adverse effects are very common.

0
|
Canadian Family Physician
Chronic PainNausea+1
A
Strong Evidence
2018
Systematic Review

National Academies Report: What Cannabis Actually Treats

Mixed Results

There is conclusive or substantial evidence that cannabis or cannabinoids are effective for chronic pain in adults, chemotherapy-induced nausea and vomiting, and spasticity associated with multiple sclerosis. Evidence for most other conditions is limited, insufficient, or absent.

0
|
European Journal of Internal Medicine
Chronic PainNausea+1
B
Moderate Evidence
2017
Patient Survey

Can Cannabis Help You Use Fewer Opioids?

Positive Results

97% of patients agreed or strongly agreed that cannabis helped them decrease the amount of opioids they use, with 92% preferring cannabis over opioids for pain management.

2,897participants
|
Cannabis and Cannabinoid Research
Chronic PainOpioid Use Disorder
A
Strong Evidence
2017
Randomized Controlled Trial

CBD for Dravet Syndrome: The Landmark Trial

Positive Results

In this groundbreaking NEJM trial, children with drug-resistant Dravet syndrome saw their monthly seizures cut from 12.4 to 5.9 with CBD—a 53% reduction. Nearly half of patients achieved at least 50% seizure reduction, and 5% became completely seizure-free.

120participants
|
New England Journal of Medicine
Epilepsy
B
Moderate Evidence
2017
Meta-Analysis

Cannabis for Chronic Pain: What 43 Clinical Trials Show

Positive with Caveats

Cannabis-based medicines might be effective for chronic pain treatment, based on limited evidence, primarily for neuropathic pain patients. However, the clinical significance of these findings is uncertain as the majority of studies did not show an effect.

2,437participants
|
Pain Physician
Chronic PainNeuropathic Pain
B
Moderate Evidence
2013
Observational Study

Long-term Cannabis Spray for Cancer Pain: Sustained Benefit, No Tolerance

Positive Results

Long-term use of THC/CBD spray was generally well tolerated, with no evidence of a loss of effect for the relief of cancer-related pain with long-term use. Patients did not seek to increase their dose over time, suggesting no tolerance development.

43participants
|
Journal of Pain and Symptom Management
Cancer PainChronic Pain
A
Strong Evidence
2010
Randomized Controlled Trial

THC Plus CBD Beats THC Alone for Cancer Pain: Landmark Trial

Positive with Caveats

THC:CBD extract is efficacious for relief of pain in patients with advanced cancer pain not fully relieved by strong opioids. THC alone showed no significant benefit over placebo.

177participants
|
Journal of Pain and Symptom Management
Cancer PainChronic Pain

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