Is it possible to switch from Vyvanse (lisdexamfetamine) and Adderall (amphetamine and dextroamphetamine) to Strattera (atomoxetine), while continuing Intuniv (guanfacine) and Zoloft (sertraline)?

Switching from Vyvanse and Adderall to Strattera While Continuing Intuniv and Zoloft

Yes, you can safely switch from Vyvanse (lisdexamfetamine) and Adderall (amphetamine/dextroamphetamine) to Strattera (atomoxetine) while continuing Intuniv (guanfacine) and Zoloft (sertraline), using a cross-taper approach over 1-2 weeks. 1

Switching Strategy

Initiation and Cross-Tapering Approach

• Start atomoxetine at 40 mg daily while gradually reducing the stimulant dose over 7-14 days 2
• Atomoxetine can be co-administered with stimulants during the switching period without undue concern for cardiovascular effects, though blood pressure and heart rate monitoring is necessary 1
• Use a slow titration schedule with divided doses to minimize adverse events during the first several weeks of treatment 1
• Titrate atomoxetine every 7-14 days to 60 mg, then 80 mg daily, with a maximum dose of 1.4 mg/kg/day or 100 mg/day (whichever is less) 2

Timeline for Evaluation

• Allow at least 6-8 weeks, possibly longer, before evaluating the overall tolerability and efficacy of atomoxetine 1
• This extended timeline is critical because atomoxetine has a different mechanism of action (selective norepinephrine reuptake inhibition) compared to the dopaminergic effects of stimulants 1

Expected Response Rates

• Approximately 50% of methylphenidate non-responders will respond to atomoxetine therapy 1
• Approximately 75% of stimulant responders will also respond to atomoxetine 1
• Nearly 90% of ADHD patients respond to either stimulants or atomoxetine if both are tried sequentially 3

Drug Interaction Considerations

Continuation of Intuniv (Guanfacine)

• Guanfacine can be safely continued during and after the switch 2
• There are no significant pharmacokinetic interactions between atomoxetine and guanfacine
• Both medications can provide complementary benefits for ADHD symptoms and executive function

Continuation of Zoloft (Sertraline)

• Sertraline can be safely continued, but requires monitoring 2
• Sertraline is a moderate CYP2D6 inhibitor, which can increase atomoxetine plasma concentrations
• This interaction may necessitate slower atomoxetine titration or lower maintenance doses
• Monitor for increased atomoxetine side effects (nausea, decreased appetite, dizziness)

Clinical Reasons for Switching

Valid Indications for Switching to Atomoxetine

• Incomplete response or non-response to stimulant treatment 1
• Poor tolerability of stimulants (41% of medication-naive adults require switching from their initial stimulant family due to poor tolerability) 4
• Co-morbid conditions such as tics, anxiety, or depression 1
• Sleep disturbances or eating problems that are exacerbated by stimulants 1
• Concerns about potential for drug abuse or diversion 1
• Need for consistent symptom coverage extending into late evening 1

Safety Profile

Atomoxetine Safety

• Atomoxetine does not appear to be associated with major congenital malformations or significant adverse obstetrical outcomes 2
• Common side effects include decreased appetite, nausea, dizziness, and fatigue, which are typically mild to moderate and transient 1
• Cardiovascular monitoring (blood pressure and heart rate) is recommended during initiation and dose adjustments 1

Discontinuation Characteristics

• Atomoxetine can be discontinued abruptly without rebound effects or discontinuation syndrome 1
• Patients may miss occasional doses without significant clinical consequences 1
• This contrasts with stimulants, which can cause rebound symptoms when discontinued abruptly

Common Pitfalls to Avoid

• Do not evaluate treatment failure too early: Allow the full 6-8 week trial period before concluding atomoxetine is ineffective 1
• Do not abruptly discontinue stimulants: Use gradual cross-tapering to minimize withdrawal symptoms and maintain symptom control during the transition 1
• Do not ignore the sertraline-atomoxetine interaction: Adjust atomoxetine dosing expectations when CYP2D6 inhibitors are present
• Do not assume equivalent immediate efficacy: Atomoxetine's therapeutic effects build gradually, unlike the immediate effects of stimulants 1