Epidiolex Dosing Calculator (Educational)
Estimate mg/day and mL/dose using standard mg/kg/day dosing concepts and a 100 mg/mL oral solution concentration.
What this epidiolex calculator does
This epidiolex calculator estimates oral solution volume from weight-based dosing. Epidiolex is typically prescribed in mg/kg/day, and the liquid concentration is commonly listed as 100 mg/mL. Families and caregivers often need quick answers to questions like:
- How many milligrams per day does this patient need at a given mg/kg/day target?
- How much should each dose be if the medicine is split twice daily?
- How many mL are required for 30 days, and how many bottles might that require?
The calculator above answers all of these by converting weight to kilograms (if needed), applying your selected dose target, and converting milligrams to milliliters.
How the math works
Core formulas
- Weight in kg = lb × 0.453592 (if entered in pounds)
- Daily dose (mg/day) = weight (kg) × selected dose (mg/kg/day)
- Dose each administration (mg) = daily dose ÷ doses per day
- mL per administration = dose each administration (mg) ÷ 100 (mg/mL)
- Total mL for supply = daily mL × number of days
Typical dose targets included in the calculator
| Dose Type | mg/kg/day Used | Notes |
|---|---|---|
| Initial | 5 | Early titration level often used when starting therapy. |
| Maintenance | 10 | Common longer-term target in many regimens. |
| Maximum (LGS/Dravet) | 20 | Common upper range in these indications. |
| Maximum (TSC) | 25 | Upper range often referenced for TSC protocols. |
Step-by-step usage
- Enter patient weight and choose kg or lb.
- Select indication (Lennox-Gastaut/Dravet or TSC).
- Choose dose type (initial, maintenance, max, or custom).
- Select doses per day (BID is common).
- Set days supply (for example, 30 days).
- Click Calculate to view mg/day, mg/dose, mL/dose, and bottle estimate.
Clinical reminders to discuss with the care team
1) Liver function monitoring
Cannabidiol-based therapy may require baseline and follow-up liver enzyme monitoring, especially during dose changes or when used with other agents that can affect liver function.
2) Drug interactions
Important interactions can occur with antiseizure medications and other therapies. Sedation and lab abnormalities may be more likely with certain combinations. Always use the pharmacy’s interaction check and the treating neurologist’s protocol.
3) Titration and tolerability
Even if two patients share the same weight, their best tolerated dose may differ. GI effects, appetite changes, fatigue, and somnolence may influence up-titration speed and target dose.
Example calculation
Suppose a 44 lb child (about 20 kg) is on 10 mg/kg/day split twice daily:
- Daily dose = 20 × 10 = 200 mg/day
- Per dose (BID) = 200 ÷ 2 = 100 mg per dose
- Per dose volume = 100 ÷ 100 = 1.0 mL per dose
- Daily volume = 2.0 mL/day
- 30-day volume = 60 mL total
FAQ
Is this an official prescribing calculator?
No. It is an educational conversion tool. Final dosing decisions belong to licensed clinicians.
Why does the tool show a caution for high custom doses?
To flag values above common indication ranges (20 mg/kg/day for LGS/Dravet, 25 mg/kg/day for TSC). This helps catch entry mistakes.
Can I use pounds directly?
Yes. The calculator converts pounds to kilograms automatically for mg/kg/day calculations.
Final note
A good epidiolex dosage calculator can reduce arithmetic errors and make refill planning easier. But it should always be paired with specialist guidance, current labeling, and patient-specific monitoring.