Can Strattera (atomoxetine) cause irregular heart rhythms?

Can Strattera (Atomoxetine) Cause Irregular Heart Rhythms?

Yes, Strattera (atomoxetine) can cause cardiovascular side effects including changes in heart rate and blood pressure, though serious irregular heart rhythms are rare at therapeutic doses. 1

Cardiovascular Effects of Atomoxetine

• Atomoxetine, a selective norepinephrine reuptake inhibitor, is commonly associated with small but statistically significant increases in heart rate and blood pressure in children, adolescents, and adults 1
• These cardiovascular effects are generally mild, time-limited, and of minor clinical significance at therapeutic doses 1
• The increase in noradrenergic tone from atomoxetine can explain some of the cardiovascular side effects observed 2

Specific Cardiovascular Concerns

• Case reports have documented instances of:

  • Syncope and orthostatic hypotension 2
  • Tachycardia (increased heart rate) 2
  • Mild QRS interval widening on ECG in overdose situations 3

• The FDA label for atomoxetine includes warnings about:

  • Potential serious cardiovascular events including sudden death, stroke, and myocardial infarction 4
  • Effects on blood pressure and heart rate, with cautions about using atomoxetine in patients with hypertension, tachycardia, or cardiovascular disease 4

Risk Assessment

• The risk for serious cardiovascular adverse events with atomoxetine is extremely low at therapeutic doses 1
• There are no reports of torsades de pointes (a specific type of life-threatening ventricular tachycardia) clearly and directly related to atomoxetine 1
• Atomoxetine is contraindicated in patients with:
  • Severe cardiovascular disorders that might deteriorate with clinically important increases in heart rate and blood pressure 4
  • Pheochromocytoma or history of pheochromocytoma 4

Monitoring Recommendations

• Patients should undergo prompt cardiac evaluation if they develop symptoms suggestive of cardiovascular problems while taking atomoxetine 4
• Particular caution is advised when considering atomoxetine for patients with:
  • Known serious structural cardiac abnormalities
  • Cardiomyopathy
  • Serious heart rhythm abnormalities
  • Other serious cardiac problems 4

Comparison with Other ADHD Medications

• Both stimulant and non-stimulant ADHD medications, including atomoxetine, have been associated with small increases in blood pressure and heart rate 1
• Unlike bupropion (another non-stimulant sometimes used for ADHD), which has been associated with specific cardiovascular malformations including left ventricular outflow tract obstruction and ventricular septal defects, atomoxetine does not appear to be associated with cardiac malformations 5

Clinical Perspective

• The benefits of treating ADHD with atomoxetine, after adequate assessment, generally outweigh the cardiovascular risks for most patients 1
• However, great caution is advised when considering atomoxetine for patients with a personal or family history of cardiovascular disease 1
• In overdose situations, atomoxetine has been associated with seizures and mild cardiac toxicity, including QRS interval widening 3

In conclusion, while atomoxetine can affect heart rate and blood pressure, serious irregular heart rhythms are uncommon at prescribed doses. However, appropriate cardiovascular screening and monitoring are recommended, especially in patients with pre-existing cardiac conditions.