Starting Dose for Strattera (Atomoxetine)
The typical starting dose for Strattera (atomoxetine) is 0.5 mg/kg/day for children and adolescents up to 70 kg, and 40 mg daily for adults and children over 70 kg. 1, 2
Dosing Guidelines by Weight
For patients ≤70 kg:
- Initial dose: 0.5 mg/kg/day
- Target dose: Increase after minimum of 3 days to approximately 1.2 mg/kg/day
- Maximum dose: 1.4 mg/kg/day or 100 mg daily (whichever is less)
- May be administered as a single morning dose or divided into morning and late afternoon/evening doses
For patients >70 kg and adults:
- Initial dose: 40 mg daily
- Target dose: Increase after minimum of 3 days to approximately 80 mg daily
- Maximum dose: 100 mg daily
- May be administered as a single morning dose or divided into morning and late afternoon/evening doses
Special Dosing Considerations
Hepatic Impairment
- Moderate impairment (Child-Pugh Class B): Reduce initial and target doses to 50% of normal dose
- Severe impairment (Child-Pugh Class C): Reduce initial and target doses to 25% of normal dose
CYP2D6 Poor Metabolizers or Patients Taking CYP2D6 Inhibitors
- Approximately 7% of the population are poor CYP2D6 metabolizers
- For patients ≤70 kg: Start at 0.5 mg/kg/day and only increase to target dose if needed after 4 weeks
- For patients >70 kg: Start at 40 mg daily and only increase to target dose if needed after 4 weeks
Administration Guidelines
- Can be taken with or without food
- Capsules should be swallowed whole, not opened
- No tapering required when discontinuing
- Safety of single doses over 120 mg and total daily doses above 150 mg has not been systematically evaluated
Monitoring Recommendations
- Monitor for common side effects, particularly during the first few months of treatment:
- Gastrointestinal effects (nausea, decreased appetite)
- Changes in blood pressure and heart rate
- Mood changes and potential suicidal ideation
- Hepatic function
Clinical Pearls
- Atomoxetine is a non-stimulant medication with no abuse potential, making it useful for patients with substance abuse concerns 3, 4
- Unlike stimulants, atomoxetine is not a controlled substance, which simplifies prescription refills
- Therapeutic effects may take longer to appear compared to stimulants (up to 4 weeks)
- Regular reassessment of long-term usefulness is recommended for patients on extended treatment 1
Remember to screen for bipolar disorder, mania, or hypomania before initiating treatment, as atomoxetine may potentially worsen these conditions.