Can children with Attention Deficit Hyperactivity Disorder (ADHD) take both Strattera (atomoxetine) and Intuniv (guanfacine)?

Combination Therapy with Strattera (Atomoxetine) and Intuniv (Guanfacine) in Children with ADHD

Yes, children with ADHD can take both Strattera (atomoxetine) and Intuniv (extended-release guanfacine) together, as extended-release guanfacine is FDA-approved as an adjunctive therapy with stimulant medications and can be used with atomoxetine when monotherapy is insufficient for symptom control. 1

Evidence for Combination Therapy

The American Academy of Pediatrics clinical practice guidelines specifically state that extended-release guanfacine has sufficient evidence to support its use as adjunctive therapy with other ADHD medications 1. While stimulants have the strongest evidence base for ADHD treatment (effect size ~1.0), non-stimulants like atomoxetine and extended-release guanfacine have slightly weaker but still significant efficacy (effect size ~0.7) 1, 2.

The combination approach is particularly useful when:

• Monotherapy with either medication alone does not provide adequate symptom control
• Different aspects of ADHD symptoms need to be targeted
• Side effects limit optimal dosing of a single medication

Mechanism of Action and Rationale

The combination makes pharmacological sense because:

• Atomoxetine (Strattera) works as a selective norepinephrine reuptake inhibitor 3
• Guanfacine (Intuniv) works as an α2-adrenergic agonist 1
• These different mechanisms can complement each other for improved symptom control

Monitoring Requirements

When using this combination, careful monitoring is essential:

• Blood pressure and heart rate:

  • Atomoxetine may increase heart rate and blood pressure
  • Guanfacine typically decreases heart rate and blood pressure
  • Monitor for potential cardiovascular effects at each dose adjustment 1

• Side effect monitoring:

  • Somnolence (both medications can cause this)
  • Gastrointestinal symptoms (more common with atomoxetine)
  • Dry mouth (more common with guanfacine)
  • Dizziness and irritability 1

• Follow-up schedule:

  • Every 3-4 weeks during dose titration
  • Every 3-6 months once stabilized 2

Dosing Considerations

• Start with one medication first:

  • Begin with either atomoxetine or guanfacine as monotherapy
  • Titrate to optimal or maximum tolerated dose
  • Add the second medication only if needed for additional symptom control

• Guanfacine discontinuation:

  • Must be tapered gradually rather than abruptly discontinued to avoid rebound hypertension 1

Important Cautions

1. Cardiovascular assessment:

   • Obtain personal and family cardiac history before starting either medication
   • Consider ECG if risk factors are present 1

2. Hepatic function:

   • Atomoxetine has rare associations with hepatic injury
   • Monitor for signs of liver dysfunction 3

3. Growth parameters:

   • Monitor height and weight regularly, as atomoxetine may affect growth trajectories in the first 1-2 years of treatment 1

4. Suicidal ideation:

   • Atomoxetine carries an FDA black box warning for increased risk of suicidal ideation 3

Special Populations

For children with comorbid conditions:

• This combination may be particularly beneficial for children with ADHD and tic disorders, as both medications have been shown not to worsen tics 4
• For preschool-aged children (4-5 years), behavioral therapy should be first-line treatment before considering medication 1, 2

Conclusion

The combination of atomoxetine and extended-release guanfacine can be an effective approach for children with ADHD who don't respond adequately to monotherapy. The American Academy of Pediatrics specifically recognizes extended-release guanfacine as an approved adjunctive therapy, making this a guideline-supported treatment option when properly monitored.