Starting Dose of Atomoxetine (Strattera) for a 42-Year-Old Woman with ADHD
The recommended starting dose of atomoxetine for a 42-year-old woman with ADHD is 40 mg once daily, with titration to a target dose of 80 mg/day or a maximum of 100 mg/day. 1
Dosing Guidelines
Atomoxetine (Strattera) is a selective norepinephrine reuptake inhibitor that is not classified as a stimulant and is indicated for the treatment of ADHD in adults. The dosing regimen for adults follows these guidelines:
- Initial dose: 40 mg once daily in the morning 2
- Titration: Dose is usually adjusted every 7-14 days; to 60 mg then 80 mg/day 2
- Maximum dose: The total maximum recommended dose is the lesser of 1.4 mg/kg/day or 100 mg/day 2, 1
Administration Considerations
- Atomoxetine can be administered either as a single daily dose in the morning or split into two evenly divided doses 3, 4
- It can be taken with or without food
- Unlike stimulant medications, atomoxetine is not a controlled substance and has negligible risk of abuse or misuse 3, 4
Dose Adjustments for Special Populations
For patients with certain conditions, dose adjustments may be necessary:
- Hepatic insufficiency: Patients with moderate hepatic impairment should receive reduced dosing (50% of the normal dose) 1
- CYP2D6 poor metabolizers: Approximately 7% of Caucasians are poor metabolizers of CYP2D6 and may require lower doses due to higher plasma concentrations 1
- Concomitant medications: If taking strong CYP2D6 inhibitors (e.g., paroxetine, fluoxetine), dose adjustments similar to those for poor metabolizers may be needed 1
Monitoring and Titration
When initiating atomoxetine therapy:
- Monitor for common side effects including dry mouth, insomnia, nausea, decreased appetite, constipation, and dizziness 4
- Check blood pressure and heart rate regularly, as atomoxetine can cause modest increases in both 3, 4
- Assess therapeutic response after 1-2 weeks on each dose level
- If symptom control is not achieved at the starting dose, increase the dose according to the titration schedule 2
Clinical Considerations
Atomoxetine may be particularly appropriate for:
- Patients at risk for substance abuse 3, 4
- Patients with comorbid anxiety disorders 1
- Patients who prefer not to take a controlled substance 3, 4
Important Precautions
- Black box warning for increased risk of suicidal ideation in children and adolescents (though this patient is an adult) 3
- Rare risk of serious liver injury 3
- Unlike stimulants, atomoxetine may cause somnolence rather than insomnia 3, 4
Atomoxetine typically takes longer to show full therapeutic effect compared to stimulants, with continued improvement over several weeks of treatment 5. Patients should be advised that, unlike stimulants which work immediately, atomoxetine may require 2-4 weeks for optimal therapeutic effect.