Management of Missed Atenolol Doses in Infantile Hemangioma
Immediate Action Required
Resume atenolol immediately at the previous dose (1 mg/kg/day as a single daily dose) without any need for cardiovascular monitoring or dose titration, as beta-blockers can be safely stopped and restarted abruptly in this population. 1
The increased fussiness after missing two days of atenolol is likely unrelated to the medication lapse itself, as beta-blockers do not cause withdrawal symptoms in infants, and the British guidelines explicitly state that "it is safe to stop propranolol abruptly (rather than weaning patients off treatment gradually) during or at the end of therapy." 1 This principle applies equally to atenolol, which has an even shorter half-life.
Key Management Points
Restart Protocol
- No cardiovascular monitoring is required when restarting atenolol after a brief interruption in a previously stable patient 1
- Resume at the full maintenance dose of 1 mg/kg/day given once daily 2
- Unlike initial dosing, there is no need for gradual titration when restarting after a short gap 2
Addressing the Fussiness
The increased irritability is more likely related to:
- Normal infant behavior unrelated to medication
- Possible hemangioma growth during the treatment gap (though unlikely after only 2 days)
- Other concurrent illness or discomfort
Monitor the hemangioma closely over the next 1-4 weeks to ensure no rebound growth has occurred, as this is the critical window when proliferation would become apparent if treatment efficacy has been compromised 2
Important Considerations About Atenolol vs. Propranolol
Why This Patient May Be on Atenolol
While propranolol remains the guideline-recommended first-line treatment at 2-3 mg/kg/day divided into three doses 1, 3, this patient is receiving atenolol, which suggests either:
- Previous intolerance to propranolol (sleep disturbance, agitation, bronchospasm) 4
- Provider preference for a β1-selective agent with fewer central nervous system effects 2, 5
Efficacy Comparison
- Propranolol achieves complete response in 85.4% vs. atenolol's 73.3% (statistically significant difference), but atenolol still demonstrates good efficacy 4
- Atenolol at 1 mg/kg/day stops hemangioma growth in 93.4% of patients within 4 weeks 2
- Both medications show similar decreases in Hemangioma Activity Score with no statistically significant difference 5, 4
Safety Profile Favors Atenolol
- Propranolol has 2.7 times higher odds of adverse events compared to atenolol 4
- Significantly more agitation and bronchial hyperreactivity with propranolol 4
- Atenolol's most common side effects are diarrhea, agitation, and sleep disturbance, but occur less frequently than with propranolol 2, 4
Ensuring Treatment Adherence
Practical Strategies
- Provide a medication dosing card to prevent future dosing errors 1
- Emphasize that atenolol is given once daily (unlike propranolol's three-times-daily dosing), which should improve adherence 2
- Ensure adequate prescription refills are available
- Schedule routine follow-up at 2-3 month intervals for stable patients 1
Duration of Treatment
- Continue treatment until at least 9-10 months of age for focal hemangiomas 1
- For large cervical hemangiomas (which may be segmental), treatment often continues until 12-18 months of age 1, 3
- If rebound growth occurs after stopping, restart for 1-3 month intervals until no further growth 1
When to Escalate Care
Consider switching to propranolol or specialist referral if:
- The hemangioma shows significant growth despite atenolol treatment over the next 4-12 weeks 2
- New complications develop (ulceration, functional impairment, airway involvement) 1
- The cervical location raises concern for PHACES syndrome (segmental facial hemangioma with potential structural anomalies) 1