Supplement
Cannabidiol, or CBD, is a non-intoxicating compound from the cannabis plant that interacts with several signaling systems in the brain, including those that help calm overactive nerve activity. People most often look at it for seizures in treatment-resistant epilepsy, and large trials found people had fewer seizures, including fewer drop seizures in Lennox-Gastaut syndrome, with the evidence rated strong. Findings for anxiety were far thinner, coming from small studies with only 57 people in total, so that evidence is limited.
Sources: PMID 40217555; PMID 29768152
- Updated
- How we grade
- 17 studies cited
- Best evidence
- Grade A
- Conditions studied
- 14
- Outcomes
- 19
- Graded outcomes
- 1010
Evidence by condition
- Strong
- Moderate
- Limited
- Very limited
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Seizure Frequency Large Improvement | Improves (the measure goes down) | Large effect | 4 studies | 1,829 people | ||
Studies that measured seizure frequency
| ||||||
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Anxiety Symptoms Moderate Improvement | Improves (the measure goes down) | Moderate effect | 5 studies | 57 people | ||
Studies that measured anxiety symptoms
| ||||||
| Attention | Improves (the measure goes up) | 60 people | ||||
| Cognition | Improves (the measure goes up) | 60 people | ||||
| Depression Symptoms | Improves (the measure goes down) | 60 people | ||||
| Mood | Improves (the measure goes up) | 60 people | ||||
| Working Memory | Improves (the measure goes up) | 60 people | ||||
Mental Resilience
- Anxiety Symptoms: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Anxiety Symptoms | Improves (the measure goes down) | 5 studies | 48 people | |||
Studies that measured anxiety symptoms
| ||||||
Paranoia
- Anxiety Symptoms: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Anxiety Symptoms | Improves (the measure goes down) | 5 studies | 32 people | |||
Studies that measured anxiety symptoms
| ||||||
Stress
- Anxiety Symptoms: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Anxiety Symptoms | Improves (the measure goes down) | 5 studies | 60 people | |||
Studies that measured anxiety symptoms
| ||||||
Tuberous Sclerosis Complex (TSD)
- Seizure Frequency: changes; see studies
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Seizure Frequency | Changes; see studies | 4 studies | 56 people | |||
Studies that measured seizure frequency
| ||||||
Multiple Sclerosis (MS)
- Pain: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Pain | Improves (the measure goes down) | 3 studies | 24 people | |||
Studies that measured pain
| ||||||
Autonomic Dysfunction
- Pain: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Pain | Improves (the measure goes down) | 3 studies | 12 people | |||
Studies that measured pain
| ||||||
Brachial plexus damage
- Pain: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Pain | Improves (the measure goes down) | 3 studies | 24 people | |||
Studies that measured pain
| ||||||
Spinal Cord Injury
- Pain: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Pain | Improves (the measure goes down) | 3 studies | 24 people | |||
Studies that measured pain
| ||||||
Surgical Recovery
- Pain: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Pain | Improves (the measure goes down) | 3 studies | 7 people | |||
Studies that measured pain
| ||||||
Schizophrenia
- Schizophrenia symptoms: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Schizophrenia symptoms | Improves (the measure goes down) | 2 studies | 124 people | |||
Crohn's Disease
- Crohn's Disease Symptoms: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Crohn's Disease Symptoms | Improves (the measure goes down) | 1 study | 20 people |
Ulcerative Colitis
- Ulcerative Colitis Symptoms: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Ulcerative Colitis Symptoms | Improves (the measure goes down) | 1 study | 60 people |
Key findings
- Seizure FrequencyImproves (the measure goes down)
- Anxiety SymptomsImproves (the measure goes down)
Shop the evidence-backed picks
Third-party tested Cannabidiol (CBD) products, in the forms the graded studies used where we can match them.
- Grade A
Links to Fullscript, iHerb or Thorne carry our referral, so we may earn a commission at no extra cost to you. Grades come from the research and never change based on what we earn. Fullscript asks for a free account before it shows its catalog and prices. Full disclosure
Studies cited
17 studies from PubMed
- Effects of Cannabidiol and Delta-9-Tetrahydrocannabinol on Emotion, Cognition, and Attention: A Double-Blind, Placebo-Controlled, Randomized Experimental Trial in Healthy Volunteers
- Cannabidiol presents an inverted U-shaped dose-response curve in a simulated public speaking test
- The effects of cannabidiol on persecutory ideation and anxiety in a high trait paranoid group
- Cannabidiol (CBD) as an Adjunctive Therapy in Schizophrenia: A Multicenter Randomized Controlled Trial
- The effects of cannabidiol (CBD) on cognition and symptoms in outpatients with chronic schizophrenia a randomized placebo controlled trial
- Low-Dose Cannabidiol Is Safe but Not Effective in the Treatment for Crohn's Disease, a Randomized Controlled Trial
- Inverted U-Shaped Dose-Response Curve of the Anxiolytic Effect of Cannabidiol during Public Speaking in Real Life
- Action of cannabidiol on the anxiety and other effects produced by delta 9-THC in normal subjects
- Effects of ipsapirone and cannabidiol on human experimental anxiety
- A Randomized, Double-blind, Placebo-controlled, Parallel-group, Pilot Study of Cannabidiol-rich Botanical Extract in the Symptomatic Treatment of Ulcerative Colitis
- Effect of Cannabidiol on Drop Seizures in the Lennox-Gastaut Syndrome
- Cannabidiol in patients with treatment-resistant epilepsy: an open-label interventional trial
- Cannabidiol as a new treatment for drug-resistant epilepsy in tuberous sclerosis complex
- The efficacy of cannabidiol for seizures reduction in pharmacoresistant epilepsy: a systematic review and meta-analysis.
- Chronic Pain Treatment With Cannabidiol in Kidney Transplant Patients in Uruguay
- Short-Term Efficacy of CBD-Enriched Hemp Oil in Girls with Dysautonomic Syndrome after Human Papillomavirus Vaccination
- A preliminary controlled study to determine whether whole-plant cannabis extracts can improve intractable neurogenic symptoms