What is the indication for Atomoxetine (Strattera)?

Atomoxetine Indication

Atomoxetine (Strattera) is indicated for the treatment of Attention-Deficit/Hyperactivity Disorder (ADHD) in children, adolescents, and adults. 1, 2

FDA-Approved Indication

Atomoxetine is a selective norepinephrine reuptake inhibitor that has been approved in many countries, including the United States and Europe, for:

• Treatment of ADHD in children and adolescents (ages 6-18)
• Treatment of ADHD in adults 1, 2

Mechanism of Action

Atomoxetine works by:

• Binding to the norepinephrine transporter, inhibiting norepinephrine reuptake
• In the prefrontal cortex, increasing both noradrenaline and dopamine levels (as norepinephrine transporters also regulate dopamine reuptake in this region)
• This mechanism differs from stimulants, making atomoxetine a non-stimulant option for ADHD treatment 1

Dosing Considerations

Dosing follows a weight-based approach:

• 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 or 100 mg/day (whichever is lower)

• For adults and children over 70 kg:

  • Initial dose: 40 mg/day
  • Target dose: 80 mg/day
  • Maximum dose: 100 mg/day 1, 2

• Available in multiple strengths: 10,18,25,40,60,80, or 100 mg capsules and as oral solution (4 mg/ml) 1, 2

Clinical Considerations

Advantages of Atomoxetine

• Non-stimulant medication (not a controlled substance)
• No abuse potential
• Can be administered once daily or split into two doses
• 24-hour symptom control
• May be particularly beneficial for patients with:
  • Risk of substance abuse
  • Comorbid anxiety
  • Comorbid tics
  • Those who prefer not to take controlled substances 1, 3

Important Safety Warnings

• Suicidal ideation risk: Higher risk in children and adolescents compared to placebo; requires close monitoring, especially during the first few months of treatment or with dose changes 1, 2

• Cardiovascular concerns: Use with caution in patients with:

  • Preexisting cardiovascular disease
  • Significant cardiac abnormalities
  • Monitor for increases in blood pressure and heart rate 1, 2

• Other warnings:

  • Severe liver injury (discontinue if jaundice or laboratory evidence of liver injury)
  • Emergent psychotic or manic symptoms
  • Effects on growth in pediatric patients (monitor height and weight)
  • Potential for priapism (requires prompt medical attention)
  • Possible allergic reactions 1, 2

Common Adverse Effects

The most frequently reported adverse effects include:

• Gastrointestinal symptoms (nausea, vomiting, abdominal pain)
• Decreased appetite
• Fatigue
• Somnolence 1

Special Populations

• CYP2D6 poor metabolizers: Approximately 7% of the population; may have higher plasma levels and longer half-lives, potentially leading to increased adverse effects 1

• Hepatic impairment: Requires dose adjustment due to altered metabolism 2

• Drug interactions: Some selective serotonin reuptake inhibitors can elevate serum atomoxetine levels 1

• Contraindications:

  • Hypersensitivity to atomoxetine
  • Use within 2 weeks of MAOI discontinuation
  • Narrow-angle glaucoma
  • Pheochromocytoma
  • Severe cardiovascular disorders 2

While atomoxetine is generally considered a second-line treatment after stimulants due to its relatively smaller effect size, it remains an important option in the pharmacological management of ADHD, particularly for patients who cannot tolerate or have contraindications to stimulant medications.