Methylphenidate Dose Equivalence: Ritalin to Concerta
The equivalent dose of Concerta to Ritalin 10 mg twice daily (20 mg total daily dose) is 18 mg of Concerta once daily.
Understanding the Equivalence
Concerta uses an osmotic pump system (OROS technology) that provides extended 12-hour coverage with once-daily dosing, while immediate-release Ritalin typically requires multiple daily doses to maintain symptom control throughout the day.
The conversion is based on the following pharmacokinetic principles:
- Ritalin 10 mg BID provides a total daily dose of 20 mg of methylphenidate
- Concerta 18 mg delivers approximately the same total daily exposure of methylphenidate but through a different delivery mechanism 1
- The OROS technology in Concerta provides an initial bolus (22% of the dose) followed by extended controlled delivery over 12 hours 2
Dose Comparison Table
| Immediate-Release Methylphenidate (Ritalin) | Extended-Release Methylphenidate (Concerta) |
|---|---|
| 5 mg BID-TID (10-15 mg/day) | 18 mg once daily |
| 10 mg BID (20 mg/day) | 18 mg once daily |
| 15 mg BID-TID (30-45 mg/day) | 36 mg once daily |
| 20 mg BID-TID (40-60 mg/day) | 54 mg once daily |
Pharmacokinetic Differences
The pharmacokinetic profiles of these formulations differ significantly:
Ritalin (immediate-release):
- Onset of action: 30 minutes after ingestion
- Peak effect: 1-2 hours
- Duration: 3-4 hours per dose 3
- Requires multiple daily dosing
Concerta (extended-release):
- Onset of action: Similar to immediate-release due to initial bolus
- Provides continuous delivery for 12 hours 2
- Once-daily administration in the morning
Clinical Considerations
Morning vs. Afternoon Coverage:
- Metadate CD (another extended-release formulation) provides better morning coverage than Concerta at near-equivalent doses
- Concerta provides better evening coverage (at 12 hours post-dose) 4
Dosing Schedule:
- Concerta should be administered once daily in the morning
- The maximum recommended daily dose is 60 mg for both children and adults 5
Food Effects:
- Unlike some other extended-release stimulants, Concerta's absorption is not significantly affected by food intake, providing consistent drug exposure regardless of meals 6
Practical Advantages of Concerta
- Reduced stigma: Eliminates the need for mid-day dosing at school or work
- Improved adherence: Once-daily dosing simplifies medication regimen
- Tamper-resistant: The OROS technology makes Concerta resistant to diversion 1
When switching from Ritalin 10 mg BID to Concerta, start with 18 mg once daily in the morning and monitor for efficacy and side effects. Titration may be necessary based on individual response, but this equivalent dose provides a reasonable starting point.