What is the starting dose of Strattera (atomoxetine) for adults and children?

Starting Dose of Strattera (Atomoxetine)

For children and adolescents weighing less than 70 kg, start atomoxetine at 0.5 mg/kg/day and increase after a minimum of 3 days to a target dose of 1.2 mg/kg/day; for those over 70 kg and adults, start at 40 mg/day and increase after a minimum of 3 days to a target dose of 80 mg/day. 1

Pediatric Dosing (Children and Adolescents)

Patients Weighing Less Than 70 kg

• Initial dose: 0.5 mg/kg/day (total daily dose) 1
• Timing of increase: Wait a minimum of 3 days before titrating upward 1
• Target dose: 1.2 mg/kg/day, administered either as a single morning dose or divided into morning and late afternoon/early evening doses 1
• Maximum dose: Do not exceed 1.4 mg/kg/day or 100 mg daily, whichever is less 1
• Single dose limit: For children under 25 kg, individual doses should not exceed 15 mg 2

Patients Weighing Over 70 kg

• Initial dose: 40 mg/day 1
• Timing of increase: Wait a minimum of 3 days before increasing 1
• Target dose: 80 mg/day 1
• Further titration: After 2-4 additional weeks at 80 mg/day, may increase to maximum of 100 mg/day if optimal response not achieved 1

Adult Dosing

• Initial dose: 40 mg/day 1
• Timing of increase: Wait a minimum of 3 days before increasing 1
• Target dose: 80 mg/day 1
• Typical titration pattern: Adjust every 7-14 days from 40 mg to 60 mg, then to 80 mg/day 2
• Maximum dose: 100 mg/day 1
• Further titration: After 2-4 additional weeks, may increase to 100 mg if response inadequate, though no data support increased effectiveness at higher doses 1

Administration Considerations

• Dosing schedule: Can be given as a single morning dose or divided into morning and late afternoon/early evening doses 1
• Food: May be taken with or without food 1
• Capsule integrity: Must be swallowed whole; do not open capsules 1
• Discontinuation: Can be stopped without tapering 1

Critical Titration Principles

Slow titration is essential to minimize adverse effects and optimize tolerability. 3

• Increase dose in smallest available increments at approximately 1-2 week intervals 3
• Maintain initial dose for at least 1-2 weeks to assess tolerability before increasing 3
• Rapid dose escalation can cause behavioral activation/agitation (motor or mental restlessness, insomnia, impulsiveness, aggression), particularly in younger patients 3
• Initial somnolence and gastrointestinal symptoms are more likely if dose is increased too rapidly 2

Special Population Dosing Adjustments

Hepatic Impairment

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

CYP2D6 Poor Metabolizers or Concurrent Strong CYP2D6 Inhibitors

For patients taking strong CYP2D6 inhibitors (paroxetine, fluoxetine, quinidine) or known CYP2D6 poor metabolizers: 1

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

Pre-Treatment Requirements

• Obtain baseline blood pressure, pulse, height, and weight in context of physical examination 2
• Document prior treatments including previous medications, dosages, duration, response, and side effects 2
• Screen for personal or family history of bipolar disorder, mania, or hypomania before initiating treatment 1

Expected Timeline for Response

• Full therapeutic effect requires 6-12 weeks, unlike stimulants which work within hours 3
• Set appropriate expectations with patients about this delayed response timeline 3
• Target dose of 1.2 mg/kg/day has shown 34-38% reduction in ADHD symptoms versus 13-15.7% with placebo 3

Common Pitfalls to Avoid

• Do not increase dose too rapidly: This is the most common error leading to intolerable side effects 2, 3
• Do not exceed maximum doses: No additional benefit demonstrated for doses higher than 1.2 mg/kg/day in children or 100 mg/day in adults 1
• Do not open capsules: Must be swallowed whole 1
• Monitor closely for suicidality, clinical worsening, and unusual behavioral changes, especially during first few months or at dose changes 3