Oral solution (Epidiolex)
- Strengths
- 100 mg/mL
- Product note
- Prescription purified cannabidiol; consumer CBD products are not equivalent. Keep administration consistent with respect to food.
Cannabidiol
Epidiolex
DailyMed-verified antiseizure indications
Indication / use
- Label / evidence summary
- Epidiolex: seizures associated with Lennox-Gastaut syndrome, Dravet syndrome, or tuberous sclerosis syndrome from age 1 year.
- Role
- Maintenance
- Class
- Human antiseizure mechanism unresolved; proposed non-CB1/CB2 pathways
Indications checked 26 September 2026. Product, route, age, and treatment-role limits apply. A DailyMed listing alone does not establish FDA approval.
- Epidiolex solution U.S. label
Lennox-Gastaut syndrome, Dravet syndrome, Tuberous sclerosis syndrome · 1 year and older · Maintenance
Formulations & strengths
U.S. products unless another country is named. Strengths are per unit or stated volume.
Brand & formulation labels
Each link names the product and formulation it covers. Archived labels do not establish current availability.
Dosing & administration
- Adult / product-specific schedule
- LGS/Dravet syndrome: 2.5 mg/kg twice daily for 1 week → 5 mg/kg twice daily; if needed, maximum 10 mg/kg twice daily. TSC: 2.5 mg/kg twice daily, increase weekly by 2.5 mg/kg twice daily to recommended 12.5 mg/kg twice daily (25 mg/kg/day).
- Pediatric
- Age ≥1 year: same syndrome-specific weight-based schedule. TSC maintenance differs from LGS/Dravet syndrome. Adjust for moderate/severe hepatic impairment.
- Titration / repeat dosing
- Use the syndrome-specific schedule above; measure the 100 mg/mL solution with a calibrated oral syringe.
Practical administration
- Product instructions
- EPIDIOLEX is 100 mg/mL. Give consistently with respect to meals because food substantially changes exposure. Measure with the supplied syringe. Use the product instructions for compatible feeding tubes and flushing.
Dose adjustment & concentrations
- Renal impairment
- No labeled dose adjustment.
- Hepatic impairment
- Reduced starting, titration, and maintenance doses in moderate/severe impairment.
- Serum reference information
- No established therapeutic range
Safety
- Boxed warning
- No boxed warning.
- Contraindications
- Hypersensitivity to cannabidiol or ingredients (including sesame seed oil).
- Serious precautions & monitoring
- ALT/AST/bilirubin before starting, at 1, 3 and 6 months and periodically thereafter; recheck within 1 month of dose changes or changes in hepatotoxic co-medications. More frequent monitoring with valproate or abnormal baseline tests. Sedation, appetite/weight loss and diarrhea.
Common / selected adverse effects
- Somnolence
- Decreased appetite
- Diarrhea
- Transaminase elevation
- Fatigue/malaise
- Insomnia/sleep disorder
Drug interactions: toxicity & clinical action
| Partner / combination | Clinical effect | Clinical action |
|---|---|---|
| Clobazam | Inhibits clearance of active N-desmethylclobazam; sedation and other benzodiazepine adverse effects increase. | Consider reducing clobazam if adverse effects occur; use levels when clinically helpful. |
| Valproate (especially with clobazam) | Greater transaminase/hepatic-injury risk; not simply an increase in valproate concentration. | Obtain and follow ALT/AST/bilirubin per label; consider reducing/stopping the contributing drug if liver tests rise. |
| Everolimus / CYP and UGT substrates | Can increase everolimus and selected substrate exposure, causing toxicity. | Review the exact substrate and label; monitor everolimus troughs and adjust dose. |
| Strong CYP3A4/CYP2C19 inducers / other sedatives | Inducers lower cannabidiol exposure; sedatives add impairment. | Review effectiveness and adjust within labeled limits; monitor sedation. |
Pregnancy & contraception
- Fetal / neonatal risk
- Human data are inadequate to define cannabidiol pregnancy risk. Animal studies found developmental toxicity, including embryofetal loss and impaired growth, at exposures similar to or greater than therapeutic exposure.
- Pregnancy / postpartum monitoring
- Epidiolex has a product-specific pregnancy surveillance program in addition to the North American ASM pregnancy registry.
Clinical evidence
Research summaries describe studied populations and outcomes; they do not add indications or constitute treatment recommendations.
Direct pivotal trial
Trial summary
- Study design / duration
- Randomized, double-blind, placebo-controlled trials in Lennox-Gastaut syndrome, Dravet syndrome, and TSC; 4-week baseline followed by approximately 14–16 weeks of treatment; syndrome-specific countable-seizure frequency was primary.
- Primary endpoint
- No single pivotal endpoint is identified in the cited source.
- Results
- Lennox-Gastaut syndrome trials: median drop-seizure reductions were approximately 37–44% with cannabidiol versus 17–22% with placebo. Dravet syndrome trial: convulsive seizures fell 39% versus 13%. TSC trial: seizure reduction was 48% versus 24%.
Trial publications
Mechanism of action
- The FDA label states that the human anticonvulsant mechanism is unknown and does not appear to be mediated through cannabinoid receptors; cannabidiol should not be portrayed as a THC-like CB1 agonist.
- GPR55-related signaling is one proposed pathway supported by experiments in a Dravet syndrome mouse model. Its contribution to clinical benefit remains unproven; other proposed molecular targets likewise require clinical validation.
Pharmacology
Adult values unless specified. Vd/F denotes apparent oral distribution volume.
Pharmacokinetics
- Bioavailability
- Absolute oral bioavailability is not specified in the U.S. label. Food substantially increases exposure; give consistently in relation to meals.
- Elimination half-life
- 56–61 hours terminal half-life after twice-daily dosing for 7 days in healthy adults. A primary study estimated an effective accumulation half-life of 10–17 hours; these are different measures.
- Volume of distribution
- Apparent oral Vz/F: 20,963–42,849 L in healthy subjects. This is an apparent oral parameter strongly influenced by bioavailability, not a physical body-fluid volume.
- Active metabolite(s)
- 7-OH-CBD is active. The current U.S. label also reports anticonvulsant activity of 7-COOH-CBD in one of two mouse models; its contribution in human epilepsy is unknown.
- Active-metabolite half-life
- 7-OH-CBD: mean terminal values 24.7 and 31.7 hours after 750 and 1,500 mg CBD twice daily for 7 days in healthy adults. 7-COOH-CBD: 21.3 and 22.0 hours in the same study; its human antiseizure contribution is unestablished.
- Protein binding
- >94%
- Metabolism / elimination
- CYP2C19/CYP3A4 and UGT1A7/1A9/2B7
Metabolite values are study-specific healthy-adult estimates, not established pediatric constants. Terminal half-life alone does not determine the dosing interval.
Molecular structure
NIH PubChem structure and record ↗
Product history
- Initial U.S. approval
- 2018
- Brands
- Epidiolex
- Manufacturer / marketer
- Jazz Pharmaceuticals (Epidiolex)
- Generic availability
- No
- Related drugs
- Purified pharmaceutical cannabidiol; not equivalent to nonprescription cannabis/CBD products.
Sources & review status
Indications and DailyMed PDFs checked: 2026-09-26. Other profile sources reviewed: 2026-09-15 · label revision noted at that review: 5/2026. This is a draft reference; final review is pending.