Switching from Strattera (Atomoxetine) to Vyvanse (Lisdexamfetamine)
You can start Vyvanse immediately after stopping Strattera without any required waiting period. 1, 2
No Washout Period Needed
Atomoxetine can be discontinued abruptly without tapering, and there is no evidence of rebound symptoms or discontinuation syndrome when stopping treatment. 1, 3, 2
No waiting period is required between stopping atomoxetine and starting lisdexamfetamine because atomoxetine is not a monoamine oxidase inhibitor (MAOI) and does not have the same drug interaction concerns. 1
The FDA label for Strattera specifically contraindicates use with MAOIs and requires a 2-week washout period only for MAOIs—not for stimulants like Vyvanse. 1
Safety of Immediate Transition
Atomoxetine and stimulants can even be co-administered during a switching period without undue concern for adverse cardiovascular effects, though blood pressure and heart rate monitoring is necessary. 3
Studies demonstrate that discontinuation of atomoxetine is well-tolerated with low incidence of discontinuation-emergent adverse events, and no statistically significant differences compared to placebo. 2
Most common adverse events from atomoxetine resolve within 3 to 53 days after discontinuation, with blood pressure and heart rate returning to baseline upon stopping the medication. 4
Clinical Approach to the Switch
Start lisdexamfetamine at standard initial dosing (typically 30 mg once daily in the morning) on the day after stopping atomoxetine, or even the same day if clinically appropriate. 3
Monitor blood pressure and heart rate during the transition, as both medications can affect cardiovascular parameters, though atomoxetine's effects resolve after discontinuation. 4, 3
Allow 6-8 weeks to fully evaluate the efficacy and tolerability of lisdexamfetamine after the switch, as this is the recommended trial period for ADHD medications. 3
Be aware that approximately 75% of patients who respond to one ADHD medication will also respond to another, though individual responses vary. 3