What is the maximum recommended dose of Strattera (atomoxetine)?

Maximum Recommended Dose of Strattera (Atomoxetine)

The maximum recommended dose of atomoxetine (Strattera) is 100 mg daily or 1.4 mg/kg/day, whichever is lower. 1, 2

Dosing Guidelines Based on Weight

Atomoxetine dosing follows a weight-based approach with different recommendations for different patient populations:

For Children and Adolescents up to 70 kg:

• Initial dose: 0.5 mg/kg/day
• Target dose: 1.2 mg/kg/day
• Maximum dose: 1.4 mg/kg/day (not to exceed 100 mg/day) 1

For Adults and Children over 70 kg:

• Initial dose: 40 mg daily
• Target dose: 80 mg daily
• Maximum dose: 1.4 mg/kg/day or 100 mg daily (whichever is lower) 1

Titration Schedule

Atomoxetine should be titrated gradually to minimize side effects:

• For children and adolescents: Increase after a minimum of 3 days to target dose 1
• For adults: Titration every 7-14 days, from 40 mg to 60 mg then to 80 mg daily 1

Special Populations

Patients with Hepatic Impairment:

• Moderate hepatic impairment: Reduce to 50% of normal dose
• Severe hepatic impairment: Reduce to 25% of normal dose 1

Administration Considerations

Atomoxetine can be administered in different ways:

• As a single daily dose in the morning 2
• As divided doses in the morning and late afternoon/evening 2

Efficacy and Dose Response

Clinical studies have demonstrated a graded dose-response relationship:

• 0.5 mg/kg/day showed intermediate efficacy between placebo and higher doses 3
• 1.2 mg/kg/day and 1.8 mg/kg/day showed superior outcomes compared to placebo 3
• The 1.8 mg/kg/day dose did not provide additional benefit over the 1.2 mg/kg/day dose 2, 3

Pharmacokinetic Considerations

The metabolism of atomoxetine is affected by CYP2D6 enzyme activity:

• CYP2D6 extensive metabolizers: plasma half-life of 5.2 hours
• CYP2D6 poor metabolizers: plasma half-life of 21.6 hours (approximately 10-fold higher plasma concentrations) 4

Clinical Pearls

• Atomoxetine is highly bound to plasma albumin (approximately 99%) 4
• Unlike stimulants, atomoxetine is not associated with abuse potential and is not a controlled substance 5, 6
• Patients with lower IQ (<85) may show reduced clinical response to atomoxetine compared to those with average cognitive functioning 7

Monitoring

• Regular monitoring of blood pressure and heart rate is recommended, as atomoxetine can cause modest increases in these parameters 5, 6
• Monitor for potential adverse effects including dry mouth, insomnia, nausea, decreased appetite, constipation, dizziness, and sweating 5, 6

Remember that while the maximum dose is 100 mg daily or 1.4 mg/kg/day (whichever is lower), the optimal dose for most patients appears to be 1.2 mg/kg/day, which provides efficacy comparable to higher doses with potentially fewer side effects.