Prescription medication · Cannabinoid (Anticonvulsant)
cannabidiol
Also sold as Epidiolex. Epidiolex is used to treat seizures linked to Lennox-Gastaut syndrome (LGS), Dravet syndrome (DS), or tuberous sclerosis complex (TSC).
Data updated 2026-05-15
- 22,227
- FDA reportsModerately reported
- 8
- InteractionsFew interactions
- Rx
- Availability
What the data shows
cannabidiol (Epidiolex) is a prescription Cannabinoid (Anticonvulsant), reported at a middle-of-the-pack volume (22,227 FDA reports), with 8 documented drug interactions.
Reporting volume reflects how widely a drug is used and studied, not how dangerous it is, a FAERS report documents a temporal association, never proof of cause.
cannabidiol (Epidiolex) is a prescription Cannabinoid (Anticonvulsant). Epidiolex is used to treat seizures linked to Lennox-Gastaut syndrome (LGS), Dravet syndrome (DS), or tuberous sclerosis complex (TSC).
Epidiolex is a medicine that contains cannabidiol. It is used to treat seizures in people with certain conditions.
Verify with FDA → · CMS NADAC pricing →
What it does
Epidiolex is used to treat seizures linked to Lennox-Gastaut syndrome (LGS), Dravet syndrome (DS), or tuberous sclerosis complex (TSC).
Common side effects
Feeling sleepy, Decreased appetite, Diarrhea
Key warnings
Epidiolex can cause liver problems.
The sections below are summarized in plain English from cannabidiol's FDA-approved prescribing information. They describe what the official label says, and are not personal medical advice.
How It Works
Epidiolex contains cannabidiol, which is a substance that may affect how the brain works. It is thought to reduce seizures by acting on certain brain chemicals. The exact way it works is not fully understood.
Side Effects (from patient reports)
Based on 22,227 FDA adverse event reports.
Most-reported reactions
Adverse reactions in FAERS for cannabidiol, by number of reports
- Seizure
Seizure
5,791 reports
- Hospitalisation 2,073
Hospitalisation
2,073 reports
- Diarrhoea 1,695
Diarrhoea
1,695 reports
- Somnolence 1,242
Somnolence
1,242 reports
- Death 1,204
Death
1,204 reports
- Fatigue 1,169
Fatigue
1,169 reports
- Weight Decreased 824
Weight Decreased
824 reports
- Weight Increased 800
Weight Increased
800 reports
- Vomiting 707
Vomiting
707 reports
- Decreased Appetite 685
Decreased Appetite
685 reports
What this shows Bars show how often each reaction was reported, not how likely it is to happen, a report records a temporal association, never proof that the drug caused it.
Reports over time
Adverse-event reports filed for cannabidiol each year to the FDA Adverse Event Reporting System (FAERS).
Year-to-year volume tracks usage, prescribing, and scrutiny, not a change in per-patient risk. Source: FDA FAERS.
Where cannabidiol sits
cannabidiol has more FDA adverse-event reports than 57% of the drugs FAERS tracks. A high position reflects how widely a drug is used and watched, not how dangerous it is.
Percentile across all drugs PlainMeds tracks by FAERS report volume. The dot is cannabidiol; the line is the median (50th percentile).
FDA Adverse Event Report Analysis
Detailed analysis of 22,227 reports from the FDA Adverse Event Reporting System (FAERS). Reports span 2010–2025.
Total Reports
22,227
Reports Mentioning Death
1,726
7.8% of reports — not proof of cause
Hospitalization Reports
6,502
Top Indication
Product Used For Unknown Indication
Gender Distribution
Age Distribution
Most Reported Adverse Reactions (FAERS)
| # | Reaction | Reports |
|---|---|---|
| 1 | SEIZURE | 5,791 |
| 3 | HOSPITALISATION | 2,073 |
| 5 | DIARRHOEA | 1,695 |
| 7 | SOMNOLENCE | 1,242 |
| 8 | DEATH | 1,204 |
| 9 | FATIGUE | 1,169 |
| 11 | WEIGHT DECREASED | 824 |
| 12 | WEIGHT INCREASED | 800 |
| 13 | VOMITING | 707 |
| 14 | DECREASED APPETITE | 685 |
| 15 | NAUSEA | 643 |
| 16 | CONDITION AGGRAVATED | 601 |
| 17 | PNEUMONIA | 593 |
| 18 | PRODUCT ADMINISTRATION INTERRUPTED | 524 |
| 19 | DRUG INTERACTION | 513 |
Reactions in Death Reports
Reactions in Hospitalization Reports
Source: FDA FAERS (Adverse Event Reporting System) Reports are voluntary and do not establish causation
Serious Warnings
Epidiolex can cause liver problems. Your doctor will check your liver before you start and during treatment. Tell your doctor right away if you feel very tired, have yellowing of the skin or eyes, dark urine, or loss of appetite. Epidiolex may also cause sleepiness or suicidal thoughts. Tell your doctor if you have any changes in mood or behavior.
Known Drug Interactions
7.2 Effect of EPIDIOLEX on Other Drugs Antiepileptic Drugs Clobazam Concomitant use of EPIDIOLEX with clobazam increases plasma concentrations of N‑desmethylclobazam, the active metabolite of clobazam [see Clinical Pharmacology ( 12.3 )], which may increase the risk of clobazam-related adverse reactions [see Adverse Reactions ( 6.1 ) and Warnings and Precautions ( 5.1 , 5.2 )]. Consider a reduction in dosage of clobazam if adverse reactions known to occur with clobazam are experienced when concomitantly used with EPIDIOLEX.
Mechanism: Cannabidiol increases the amount of an active byproduct of clobazam in your blood, which can lead to more side effects.
For CYP2C19 substrates (e.g., clopidogrel) where efficacy is mainly due to their active metabolite(s), concomitant use of EPIDIOLEX may decrease plasma concentration of the active metabolite(s) and may therefore decrease efficacy.
Mechanism: Cannabidiol interferes with how your body activates clopidogrel, which can make the medicine less effective at preventing blood clots.
Increases in exposure of certain CYP1A2 substrates (e.g., theophylline, tizanidine) may be observed when concomitantly used with EPIDIOLEX.
Mechanism: Cannabidiol slows down the process your body uses to break down tizanidine, which can lead to higher levels of the drug in your blood.
7.3 Concomitant Use of EPIDIOLEX and Valproate Concomitant use of EPIDIOLEX and valproate increases the incidence of liver enzyme elevations [see Warnings and Precautions ( 5.1 )]. If such elevations occur, consider discontinuation or reduction of EPIDIOLEX and/or concomitant valproate.
Mechanism: Taking these two medicines together can cause your liver enzymes to rise, which may indicate liver irritation.
( 7.2 ) 7.1 Effect of Other Drugs on EPIDIOLEX Strong CYP3A4 or CYP2C19 Inducers Concomitant use with a strong CYP3A4 and CYP2C19 inducer (rifampin 600 mg once daily) decreased cannabidiol and 7‑OH‑CBD plasma concentrations by approximately 32% and 63%.
Mechanism: Rifampin makes your body clear cannabidiol much faster than usual, which makes the medicine less effective.
This is a plain-language summary of FDA-label interaction records and does not provide individual medication-combination directions.
Common Questions
What should I do if I experience side effects?
Can I drive while taking Epidiolex?
Will Epidiolex cure my seizures?
How long will I need to take Epidiolex?
Can I take other medicines with Epidiolex?
What if I accidentally take too much Epidiolex?
How will I know if Epidiolex is working?
Does Epidiolex contain THC?
Can children take Epidiolex?
How should I measure the dose?
What are the common side effects of cannabidiol?
Does cannabidiol interact with other medications?
What drug class is cannabidiol?
What pregnancy or breastfeeding source fields are listed for cannabidiol?
Related Medications in Cannabinoid (Anticonvulsant)
Other drugs grouped near cannabidiol - same-class peers and common alternatives.
brivaracetam
Briviact
Brivaracetam is a medicine used to treat partial-onset seizures.
Compare with cannabidiol →
carbamazepine
Tegretol
Carbamazepine is a medicine used to control seizures and treat nerve pain.
Compare with cannabidiol →
cenobamate
Xcopri
Xcopri is a medicine used to treat partial-onset seizures in adults.
Compare with cannabidiol →
clobazam
Onfi, Sympazan
Clobazam oral suspension is a medicine used with other medicines to treat seizures caused by Lennox-Gastaut syndrome.
Compare with cannabidiol →
clonazepam
Klonopin
Clonazepam is a medicine that belongs to the benzodiazepine class.
Compare with cannabidiol →
Compare beyond drug class
Nationwide peers by FAERS volume & death-report share
Two PlainMeds-derived comparison paths for cannabidiol: nearest FDA FAERS report volume and nearest death-report share among drugs with at least 1,000 logged reports, excluding same-class neighbors listed above. Counts reflect reporting volume, not proven individual harm.
Similar FAERS report volume
Nearest drugs by total FAERS reports. This record: 22,227.
Similar death-report share
Nearest drugs by FAERS death-report share. This record: 7.77%.
- cefdinir Δ 0.01 pts · 7,348 reports · Third-Generation Cephalosporin 7.77%death share
- dofetilide Δ 0.01 pts · 10,302 reports · Class III Antiarrhythmic 7.76%death share
- methocarbamol Δ 0.01 pts · 21,191 reports · Muscle Relaxant 7.75%death share
- etodolac Δ 0.04 pts · 5,880 reports · Nonsteroidal Anti-Inflammatory Drug (NSAID) 7.81%death share
Medication Guides
Understanding Drug Interactions
How CYP450 enzymes, inhibitors, and inducers affect your medications
Generic vs Brand Name Drugs
FDA requirements, cost savings, and when the difference matters
Narrow Therapeutic Index Drugs
FDA bioequivalence and label-record context for narrow therapeutic index medicines
Common Drug Interactions
Dangerous medication combinations and how to protect yourself
Save on cannabidiol
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What the FDA Data Shows for cannabidiol
The FDA label for cannabidiol (sold under brand names such as Epidiolex) classifies it as a prescription-only medication in the Cannabinoid (Anticonvulsant) class. Epidiolex is used to treat seizures linked to Lennox-Gastaut syndrome (LGS), Dravet syndrome (DS), or tuberous sclerosis complex (TSC). Official labeling lists 10 commonly reported side effects, including Feeling sleepy, Decreased appetite, Diarrhea.
Post-market surveillance from the FDA Adverse Event Reporting System (FAERS) captures real-world experience. For this drug, FAERS contains 22,227 voluntary reports. The database also lists 8 documented drug interactions derived from FDA labeling, with the top-flagged interaction rated moderate severity. Acquisition-cost data is surveyed weekly by CMS and updated as manufacturers report changes.
Report counts do not establish causation, a FAERS entry documents a temporal association, not proof that the drug produced the outcome. Widely prescribed medications naturally accumulate more reports than niche therapies, so raw totals must be interpreted alongside total exposure. Shortage status, recall history, and patent information are separate source-record fields. This page is a public FDA/CMS registry and does not provide medical, treatment, substitution, or medication-change directions.
Data Sources
Drug labeling: FDA Drug Labels (SPL/DailyMed). Adverse events: FDA Adverse Event Reporting System (FAERS).
FAERS reports are voluntary and do not establish causation. Drug interactions are derived from FDA labeling and clinical references. This registry does not provide medication decisions.
Last updated: July 31, 2025
PlainMeds is rendered directly from FDA openFDA/FAERS extracts, DailyMed labels, and CMS drug-pricing files, no number is typed in by an editor. FAERS counts, recalls, shortages, and price figures on this page are queried live from those federal extracts. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2026-05-15. Primary sources: openFDA / FAERS, DailyMed and CMS Part B ASP.
Read our methodology - how this data is sourced, computed, and verified.
Data currency: FDA FAERS adverse-event reports through 2025, CMS NADAC acquisition-cost pricing effective December 2024, compiled from the source snapshot dated . See our methodology for per-source dates and refresh cadence. Spot a figure that looks wrong? Report a data issue.
All federal data sources used on this page
- FDA Orange Book - approved drug products with therapeutic equivalence. accessdata.fda.gov/cder/ob
- FDA DailyMed - NIH-hosted drug labeling for FDA-approved meds. dailymed.nlm.nih.gov
- FDA Adverse Event Reporting System (FAERS) - post-marketing safety surveillance. fda.gov/drugs/faers
- NLM RxNorm - standardized clinical drug nomenclature. nlm.nih.gov/research/umls/rxnorm
- CMS Medicare Part B Drug Average Sales Price Files - federal drug pricing data. cms.gov/medicare/part-b-drugs/asp
- FDA Drug Shortages Database - current and resolved drug shortage tracking. accessdata.fda.gov/drugshortages