Direct Answer: No Established Dose Equivalency
There is no established direct dose equivalency between Vyvanse 70 mg and Concerta 72 mg, and attempting mathematical conversions between these medications is unreliable and not recommended. 1
Why Direct Conversion Is Not Possible
Lisdexamfetamine (Vyvanse) and methylphenidate (Concerta) are fundamentally different medication classes with distinct mechanisms of action and pharmacokinetics that make direct dose equivalency calculations impossible. 1
Vyvanse is a prodrug that is converted to d-amphetamine after ingestion, which then competitively inhibits dopamine and norepinephrine transporters while also promoting the release of these neurotransmitters. 2
Concerta delivers methylphenidate through an osmotic pump system (OROS technology) that produces a rapid rise followed by increasing plasma concentrations peaking 7-9 hours after administration. 3
The pharmacokinetic profiles differ substantially: lisdexamfetamine has a longer lag time (approximately 0.6 hours longer) and reaches peak levels approximately 1.1 hours later compared to immediate-release amphetamine formulations. 4
Recommended Conversion Approach
When switching from Vyvanse 70 mg to Concerta, start at Concerta 36 mg once daily in the morning, regardless of the Vyvanse dose. 1
This empiric starting approach is necessary because:
- Individual response varies significantly between amphetamine and methylphenidate classes. 1
- Stimulant equivalency tables are unreliable for cross-class switches. 1
- Therapeutic effects occur within hours of the first Concerta dose, allowing for rapid assessment of response. 1
Titration Strategy After Conversion
After starting Concerta 36 mg:
- Assess response within hours of the first dose, as immediate therapeutic effects are expected and full clinical benefit does not require weeks of treatment. 1
- Titrate based on clinical response, not on mathematical dose ratios from the previous Vyvanse dose. 1
- Concerta can be increased in increments, with a maximum dose of 72 mg daily available. 5
Safety Monitoring During Conversion
- Monitor blood pressure and heart rate closely, as cardiac conduction effects can occur with methylphenidate. 1
- Avoid taking Concerta with high-fat meals if consistent timing relative to food intake cannot be maintained, as this can affect absorption. 1
Common Pitfall to Avoid
Do not assume that because a patient was on Vyvanse 70 mg (the maximum dose), they will need Concerta 72 mg (also a maximum dose). 1 This assumption of equivalent efficacy at maximum dose ratios is a critical error that ignores the fundamental pharmacological differences between these medication classes.