What is the recommended dosing for Strattera (atomoxetine)?

Strattera (Atomoxetine) Dosing

Strattera should be initiated at 0.5 mg/kg/day in children and adolescents up to 70 kg (or 40 mg/day in those over 70 kg and adults), increased after a minimum of 3 days to a target dose of 1.2 mg/kg/day (or 80 mg/day), with a maximum of 1.4 mg/kg/day or 100 mg daily, whichever is less. 1

Initial Dosing

Children and Adolescents ≤70 kg

• Start at 0.5 mg/kg/day total daily dose 1
• Increase after a minimum of 3 days to target dose of 1.2 mg/kg/day 1
• Maximum dose: 1.4 mg/kg/day or 100 mg daily, whichever is less 1
• Can be given as single morning dose or divided into morning and late afternoon/evening doses 1

Children and Adolescents >70 kg and Adults

• Start at 40 mg/day 1
• Increase after a minimum of 3 days to target dose of 80 mg/day 1
• After 2-4 additional weeks, may increase to maximum of 100 mg/day in patients without optimal response 1
• Can be given as single morning dose or divided doses 1

Titration Principles

Slow, gradual titration is critical to minimize adverse effects and avoid behavioral activation. 2

• Maintain initial dose for at least 1-2 weeks before increasing to assess tolerability 2
• Increase by small increments (typically 10-25 mg) no more frequently than every 1-2 weeks 2
• Doses higher than 1.2 mg/kg/day have not demonstrated additional benefit in children and adolescents 1
• Doses above 80 mg/day have limited evidence for increased effectiveness in adults 1

Special Populations Requiring Dose Adjustment

Hepatic Impairment

• Moderate hepatic impairment (Child-Pugh Class B): Reduce initial and target doses to 50% of normal dose 1
• Severe hepatic impairment (Child-Pugh Class C): Reduce initial and target doses to 25% of normal dose 1

CYP2D6 Poor Metabolizers or Concurrent Strong CYP2D6 Inhibitors

When using strong CYP2D6 inhibitors (paroxetine, fluoxetine, quinidine) or in known CYP2D6 poor metabolizers:

• Children/adolescents ≤70 kg: Start at 0.5 mg/kg/day, increase to usual target of 1.2 mg/kg/day only if symptoms fail to improve after 4 weeks and initial dose is well tolerated 1
• Children/adolescents >70 kg and adults: Start at 40 mg/day, increase to usual target of 80 mg/day only if symptoms fail to improve after 4 weeks and initial dose is well tolerated 1

Critical Safety Monitoring

Behavioral Activation Risk

• Behavioral activation/agitation (motor/mental restlessness, insomnia, impulsiveness, aggression) can occur early in treatment or with dose increases 2
• Younger patients are more susceptible to behavioral activation with rapid dose escalation 2
• If side effects occur, return to previous well-tolerated dose 2

Mandatory Monitoring

• Screen for bipolar disorder, mania, or hypomania (personal or family history) before initiating treatment 1
• Monitor closely for suicidality, clinical worsening, and unusual behavioral changes, especially during first few months or at dose changes 2
• Common adverse effects include nausea, vomiting, fatigue, decreased appetite, abdominal pain, and somnolence 2

Maintenance Treatment

• Atomoxetine can be continued long-term for patients who achieve response 1
• No tapering required when discontinuing 1
• Periodically reevaluate long-term usefulness for individual patients 1
• Capsules must be taken whole, not opened 1

Administration Flexibility

• May be taken with or without food 1
• Single daily morning dose provides symptom control throughout waking hours into evening 3, 4
• Divided dosing (morning and late afternoon/evening) is an alternative option 1