Switching from Vyvanse 30mg to Adderall XR
When switching from Vyvanse (lisdexamfetamine) 30mg to Adderall XR, start with Adderall XR 10mg once daily in the morning, then titrate at weekly intervals based on symptom control and tolerability. 1
Rationale for Starting Dose
The FDA-approved Adderall XR labeling explicitly states that when "switching from another medication," the recommended starting dose is 10mg/day for children (ages 6-12) and adolescents (ages 13-17), or 20mg/day for adults 1. This conservative approach is warranted because:
- No direct dose equivalency exists between lisdexamfetamine and mixed amphetamine salts. While both are amphetamine-based stimulants, lisdexamfetamine is a prodrug that requires enzymatic conversion to d-amphetamine, resulting in different pharmacokinetic profiles 2
- Individual response varies significantly - research shows that 41% of medication-naive adults require switching between stimulant families due to poor tolerability, and this cannot be predicted by baseline characteristics 3
- Starting lower minimizes risk of adverse cardiovascular effects, insomnia, and appetite suppression
Titration Protocol
Week-by-week approach:
- Week 1: Start Adderall XR 10mg (or 20mg for adults) once daily upon awakening
- Week 2+: Increase in 5-10mg increments weekly until optimal symptom control is achieved 1
- Maximum doses: 30mg/day for children, 20mg/day for adolescents (though can increase after one week if needed), no specified maximum for adults 1
Critical Implementation Details
Timing considerations:
- Administer upon awakening to avoid insomnia 1
- Avoid afternoon doses due to extended-release formulation
- The medication can be taken with or without food 1
Monitoring requirements:
- Assess ADHD symptoms weekly during titration
- Check blood pressure and pulse at each visit (quarterly for adults on maintenance) 4
- Document response, side effects, and adherence at each adjustment 4
Common pitfall to avoid: Do not assume dose equivalency. Vyvanse 30mg does not equal any specific Adderall XR dose. Research demonstrates that even patients on adequate amphetamine doses who remained symptomatic showed significant improvement when switched to lisdexamfetamine, and vice versa 5. This underscores the importance of individualized titration rather than mathematical conversion.
Safety Considerations
Before initiating the switch:
- Obtain baseline vital signs (blood pressure, pulse, height, weight) 4
- Screen for contraindications: cardiovascular disease, moderate-to-severe hypertension, hyperthyroidism, glaucoma, agitated states, history of stimulant abuse 1
- Assess for substance abuse risk, particularly in adolescents 6
No washout period is required when switching between stimulant medications in stable patients, though clinical judgment should guide this decision based on tolerability concerns.
Expected Outcomes
Both medications are highly effective amphetamine-based stimulants. While one small crossover study suggested slightly greater improvements on some executive function measures with lisdexamfetamine 7, and another showed higher rates of "very much improved" ratings in children 8, these differences are modest and may not be clinically meaningful for all patients. The key is systematic titration to the optimal dose of whichever medication is being used.