Pharmacokinetic Profile of Concerta (Methylphenidate OROS)
Concerta begins working within 1-2 hours after ingestion, reaches peak plasma concentration at 6-8 hours, and provides therapeutic effects for a full 12 hours. 1, 2
Onset of Action
- Concerta demonstrates clinical effects within 1-2 hours after morning administration, which is slower than immediate-release methylphenidate (30 minutes) but still provides relatively rapid symptom control 1, 2
- The OROS delivery system releases an initial bolus of methylphenidate from the outer coating, accounting for this early onset 2
- This delayed onset compared to immediate-release formulations is a common pitfall—patients and families should be counseled that Concerta does not work as immediately as standard methylphenidate 1
Peak Plasma Concentration
- Peak plasma concentration (Tmax) occurs at approximately 6-8 hours post-dose, which differs markedly from immediate-release methylphenidate that peaks at 1-2 hours 3, 4, 2
- The OROS technology produces an ascending plasma concentration pattern throughout the day rather than the sharp peaks seen with immediate-release formulations 5
- Mean Cmax values are approximately 9.1 ng/mL for a 20 mg dose under fasted conditions 3
- Food increases Cmax by approximately 13% and delays Tmax by about 1 hour, though this is not clinically significant enough to require specific timing relative to meals 3
Overall Duration of Effect
- Concerta provides 12 hours of continuous therapeutic coverage from a single morning dose, eliminating the need for school-time dosing 1, 6, 2
- This extended duration is achieved through the osmotic pump (OROS) delivery system that maintains ascending drug levels throughout the day 5
- The 12-hour duration was demonstrated in laboratory school studies showing efficacy matching methylphenidate immediate-release given three times daily 5, 2
- The terminal half-life of methylphenidate itself remains approximately 2-3 hours, but the controlled-release mechanism extends the clinical effect well beyond the elimination half-life 3, 7
Clinical Implications
- The ascending plasma concentration pattern overcomes acute tolerance (tachyphylaxis) that can develop with repeated immediate-release doses throughout the day 5, 2
- Concerta 18 mg once daily is approximately equivalent to methylphenidate immediate-release 5 mg three times daily 5, 1
- Administer in the morning to minimize insomnia, as effects persist into the evening hours 5, 6
- The OROS capsule cannot be crushed, chewed, or divided—it must be swallowed whole to maintain the controlled-release properties 6