Atomoxetine (Strattera): Uses, Dosage, Side Effects, and What to Expect

Atomoxetine (brand name: Strattera) is a selective norepinephrine reuptake inhibitor (nri). Atomoxetine selectively blocks the norepinephrine transporter (NET) in the prefrontal cortex. Because NET also clears dopamine in the prefrontal cortex (where dopamine transporters are sparse), atomoxetine increases both norepinephrine and dopamine in this region — improving executive function and attention. Crucially, it does NOT increase dopamine in the nucleus accumbens (the reward center), which is why it has no abuse potential and is not a controlled substance. This makes it the preferred option for patients with substance use risk.

• Attention-Deficit/Hyperactivity Disorder (ADHD) in children 6+ and adults

Common off-label uses:

• ADHD with comorbid anxiety (may treat both)
• ADHD with comorbid tic disorders
• ADHD in patients with substance use history
• Adult ADHD when stimulants are contraindicated or declined

Children/adolescents <70 kg: start 0.5 mg/kg/day for 3 days, then 1.2 mg/kg/day (max 1.4 mg/kg or 100 mg). Adults and children >70 kg: start 40 mg/day for 3 days, then 80 mg/day, max 100 mg. Can be taken once daily (morning) or split into morning and late afternoon. CYP2D6 poor metabolizers: start lower, max 80 mg.

Unlike stimulants, atomoxetine requires weeks for full effect. Partial improvement may begin in 1-2 weeks, but full therapeutic effect takes 4-6 weeks (some patients up to 8-12 weeks). This is a key difference from stimulants, which work within hours of the first dose.

• Decreased appetite (less than stimulants)
• Nausea and vomiting
• Fatigue or drowsiness
• Abdominal pain
• Dry mouth
• Constipation
• Dizziness
• Insomnia or somnolence
• Mood swings (early treatment)

• Suicidal ideation in children and adolescents (FDA black box warning — 0.4% vs 0% placebo)
• Hepatotoxicity (rare but potentially severe — discontinue if jaundice develops)
• Cardiovascular effects (increased heart rate and blood pressure)
• Severe allergic reactions (rare)
• Priapism (rare)
• Growth suppression (less than stimulants)

CYP2D6 substrate — strong CYP2D6 inhibitors (fluoxetine, paroxetine, quinidine) significantly increase levels. MAOIs contraindicated. Use caution with other sympathomimetics and drugs that lower seizure threshold. Beta-blockers may have additive cardiovascular effects.

Category C. Limited data. Not recommended during pregnancy unless benefits clearly outweigh risks.

No withdrawal syndrome. Can be stopped abruptly, though ADHD symptoms return. Some recommend gradual reduction to distinguish rebound from return of baseline symptoms.