Strattera (Atomoxetine) Dosing for Adults
For adults with ADHD, start Strattera at 40 mg daily for a minimum of 3 days, then increase to the target dose of 80 mg daily, with a possible increase to 100 mg after 2-4 additional weeks if response is suboptimal. 1
Initial Dosing Strategy
The FDA-approved dosing regimen is straightforward:
- Day 1-3: 40 mg once daily
- Day 4 onward: 80 mg daily (either as a single morning dose or divided into morning and late afternoon/evening doses)
- Week 2-4+: May increase to maximum 100 mg daily if optimal response not achieved 1
The medication can be taken with or without food and should be swallowed whole without opening the capsule 1.
Critical Timing Considerations
Allow 4-6 weeks at the target dose before judging efficacy. 2 This is a common pitfall—many clinicians and patients abandon atomoxetine prematurely. The medication requires adequate time at therapeutic doses to demonstrate full benefit.
After 2-4 additional weeks at 80 mg, if symptoms remain inadequately controlled, increase to 100 mg daily. There is no data supporting increased effectiveness at doses higher than 100 mg 1.
Common Dosing Errors to Avoid
Real-world data reveals that adult patients frequently receive suboptimal doses averaging only 60 mg/day, well below the recommended 80 mg target 2. This underdosing likely contributes to treatment failures that could have been avoided with proper titration.
Do not stop at 40 mg. This is a starting dose, not a therapeutic dose. The 40 mg dose was specifically designed as an initial tolerability step before reaching the evidence-based target of 80-100 mg 1.
Dosing Adjustments for Special Populations
Hepatic impairment:
- Moderate (Child-Pugh B): Reduce initial and target doses to 50% of normal
- Severe (Child-Pugh C): Reduce to 25% of normal 1
CYP2D6 poor metabolizers or patients on strong CYP2D6 inhibitors (paroxetine, fluoxetine, quinidine): Start at 40 mg and increase to 80 mg only after 4 weeks if tolerated and needed 1
Renal impairment: No adjustment needed, even in end-stage renal disease 1
Maintenance Treatment
Once response is achieved, continue the effective dose indefinitely. Atomoxetine can be discontinued without tapering 1. Periodically reassess the ongoing need for pharmacological treatment, but recognize that extended treatment is often necessary for sustained benefit 1.
Tolerability Profile
The most common adverse events include dry mouth, nausea, and decreased appetite 3. Discontinuation rates due to adverse events are relatively low (6.7-9.3%) 3, 4. Setting realistic expectations about initial side effects and the delayed onset of therapeutic benefit improves adherence through the titration phase.