Strattera (Atomoxetine) Dosing for ADHD
Start atomoxetine at 40 mg orally once daily, then titrate every 7-14 days to 60 mg and then 80 mg daily, with a maximum dose of 1.4 mg/kg/day or 100 mg/day (whichever is lower). 1, 2
Starting Dose
- Begin with 40 mg orally once daily 1, 2
- This initial dose applies to both adults and children/adolescents weighing >70 kg 3
- For children and adolescents <70 kg, the starting dose should be approximately 0.5 mg/kg/day 4
Titration Schedule
- Increase dose every 7-14 days in a stepwise fashion 1, 2
- Progress from 40 mg daily → 60 mg daily → 80 mg daily 1
- The target therapeutic dose is 1.2 mg/kg/day, which appears as effective as higher doses 2, 4
- Real-world data show many patients receive suboptimal dosing (averaging ~60 mg/day in adults), which may lead to treatment failure 5
Maximum Dose
- The maximum recommended dose is the lesser of 1.4 mg/kg/day OR 100 mg/day 1, 2
- This ceiling applies regardless of patient weight 3
Duration Before Assessing Efficacy
- Maintain the target dose for 4-6 weeks before judging treatment response 5
- Unlike stimulants which work immediately, atomoxetine requires daily dosing to build therapeutic levels 6
- Premature dose adjustments or discontinuation due to perceived lack of efficacy is a common pitfall 5
Dosing Frequency
- Atomoxetine can be administered once daily or divided into two evenly split doses 7, 8
- Once-daily morning dosing provides symptom control throughout waking hours and into the next morning 9
Critical Safety Monitoring
- Monitor closely for suicidal ideation, clinical worsening, and unusual behavioral changes, especially during the first few months or at dose changes 2
- Assess for preexisting cardiovascular disease or cardiac abnormalities before initiating treatment 2
- Monitor heart rate and blood pressure, as modest increases may occur but are generally well tolerated 7, 8
Special Populations
Poor CYP2D6 Metabolizers
- Approximately 7% of patients are poor metabolizers, resulting in significantly higher plasma levels and longer half-lives 2
- Consider lower doses or slower titration in these patients 2
- Concomitant SSRIs can elevate atomoxetine levels and may require dose adjustment 2
Renal Insufficiency
- No dose adjustment needed for patients with renal insufficiency, including end-stage renal disease 3
Comorbid Conditions
- Atomoxetine does not worsen tics in patients with ADHD and comorbid Tourette's disorder or chronic tic disorders 3
- Atomoxetine does not worsen anxiety in patients with ADHD and comorbid anxiety disorders 3
- Preliminary data support efficacy in oppositional-defiant disorder and conduct disorder 9
Common Pitfalls to Avoid
- Underdosing: Many clinicians stop at 60 mg/day rather than reaching the 80-100 mg target dose, leading to suboptimal outcomes 5
- Premature discontinuation: Judging efficacy before 4-6 weeks at target dose results in missed treatment opportunities 5
- Expecting immediate effects: Unlike stimulants, atomoxetine requires consistent daily dosing and time to reach steady state 6
- Forgetting suicide risk monitoring: The black box warning for suicidal ideation requires vigilant monitoring, particularly early in treatment 2
Advantages Over Stimulants
- Not a controlled substance with negligible abuse potential 7, 8, 9
- No evidence of withdrawal syndrome or symptom rebound upon discontinuation 9
- Useful in patients at risk for substance abuse or who prefer non-controlled medications 7, 8
- Provides continuous 24-hour symptom coverage with once-daily dosing 9