What is the protocol for transitioning a patient from Adderall (amphetamine and dextroamphetamine) to Strattera (atomoxetine) for Attention Deficit Hyperactivity Disorder (ADHD) management?

Protocol for Transitioning from Adderall to Strattera

Direct Switching Without Washout Period

You can initiate atomoxetine (Strattera) immediately while cross-tapering Adderall without requiring a washout period, as there are no significant pharmacokinetic interactions between stimulants and atomoxetine. 1

The most practical approach involves starting atomoxetine while gradually reducing the stimulant dose over 1-2 weeks, allowing for continuous ADHD symptom coverage during the transition. 1

Step-by-Step Transition Protocol

Week 1: Initiate Atomoxetine with Full Stimulant Dose

• Start atomoxetine at 0.5 mg/kg/day (or 40 mg/day for adults) as a single morning dose while maintaining the current Adderall dose. 2, 3
• Continue full Adderall dose during the first week to maintain symptom control while atomoxetine begins to take effect. 1
• Use divided dosing (morning and evening) if gastrointestinal side effects or somnolence occur with atomoxetine. 4, 3

Week 2-3: Begin Adderall Taper

• Reduce Adderall by 25-50% while increasing atomoxetine to target dose of 1.2 mg/kg/day (or 60-100 mg/day for adults). 2, 1
• Monitor for withdrawal symptoms from Adderall reduction, though abrupt discontinuation of stimulants does not typically cause significant withdrawal syndromes. 1
• Titrate atomoxetine every 7-14 days based on tolerability, with maximum dose of 1.4 mg/kg/day or 100 mg/day, whichever is lower. 2, 3

Week 3-4: Complete Stimulant Discontinuation

• Discontinue Adderall completely once atomoxetine reaches therapeutic dosing. 1
• Adderall can be stopped abruptly without tapering if needed, as stimulants do not require gradual discontinuation. 1

Critical Timeline Expectations

Set realistic expectations that atomoxetine requires 6-12 weeks to achieve full therapeutic effect, compared to stimulants which work within days. 4, 2

• Initial ADHD symptom improvement may be observed within 2-4 weeks, but maximal benefit takes substantially longer. 4
• Plan for a trial period of at least 6-8 weeks before evaluating overall efficacy and tolerability. 1
• Patients will likely experience reduced ADHD symptom control during the transition period, as atomoxetine has smaller effect sizes (0.7) compared to stimulants (1.0). 2

Essential Monitoring Parameters

Cardiovascular Monitoring

• Measure blood pressure and heart rate at baseline, weekly during titration, and regularly during maintenance. 4, 2
• Both medications cause small increases in blood pressure and heart rate, but co-administration during cross-taper does not produce additive cardiovascular effects requiring dose adjustment. 1

Psychiatric Monitoring

• Screen for suicidal ideation at every visit, particularly during the first few months and with dose changes, due to FDA black box warning for atomoxetine. 2, 3
• Monitor for clinical worsening, unusual behavioral changes, and emergence of depressive symptoms. 4, 3

Growth and Appetite Monitoring

• Track height and weight regularly, though atomoxetine causes less appetite suppression and fewer growth problems than stimulants. 4
• Initial weight loss may occur but typically returns to normal in longer-term treatment. 3

Sleep Pattern Assessment

• Atomoxetine is less likely to cause insomnia compared to stimulants and may improve sleep disturbances. 3
• Consider evening-only dosing if daytime somnolence occurs, as this is a common adverse effect. 4

Clinical Scenarios Favoring This Switch

Atomoxetine should be prioritized as first-line over stimulants in patients with active substance use disorders, as it has no abuse potential and is not a controlled substance. 4, 3

Additional scenarios where switching to atomoxetine is particularly appropriate include:

• Comorbid tic disorder or Tourette's syndrome, where atomoxetine may be considered first-line treatment. 4, 5
• Severe stimulant-induced insomnia that persists despite dose timing adjustments. 2
• Comorbid anxiety disorders, where atomoxetine has supporting evidence. 4, 3
• Concerns about stimulant diversion or misuse in adolescents or adults. 3
• Need for "around-the-clock" symptom coverage extending into late evening. 4, 1

Common Pitfalls to Avoid

Do not assume atomoxetine will provide equivalent ADHD symptom control to Adderall, as head-to-head trials demonstrate stimulants are significantly more effective. 4, 2

• Atomoxetine is significantly less effective than extended-release amphetamine formulations, with medium-range effect sizes compared to stimulants' large effect sizes. 4, 3
• Approximately 50% of methylphenidate non-responders will respond to atomoxetine, but this also means 50% will not. 1
• Do not discontinue atomoxetine prematurely before the 6-12 week trial period, as therapeutic effects develop gradually. 4, 1
• Do not split atomoxetine doses unnecessarily; once-daily morning dosing is effective and preferred for adherence unless adverse effects require divided dosing. 4, 3
• Avoid combining atomoxetine with strong CYP2D6 inhibitors (like paroxetine) without dose adjustment, as this significantly increases atomoxetine exposure. 3

Alternative Approach: Conservative Sequential Switch

If concerns exist about co-administration or if the patient prefers not to take multiple medications simultaneously:

• Taper Adderall over 3-7 days (though abrupt discontinuation is also acceptable). 1
• Start atomoxetine immediately after final Adderall dose without washout period. 1
• Accept that there will be a gap of 6-12 weeks with suboptimal ADHD symptom control while atomoxetine reaches full effect. 4

This conservative approach is less preferred because it leaves patients without adequate ADHD treatment for an extended period, potentially impacting functioning in multiple life domains. 1