Urticaria Management in Children
Start with a second-generation non-sedating H1 antihistamine (cetirizine, loratadine, or fexofenadine) at standard age-appropriate dosing as first-line therapy for all forms of pediatric urticaria. 1, 2
First-Line Treatment: Second-Generation Antihistamines
Cetirizine is the preferred initial agent because it reaches maximum concentration fastest, providing more rapid symptom relief compared to other second-generation antihistamines. 1
Age-Appropriate Dosing:
- Ages 2-5 years: Cetirizine 2.5 mg once or twice daily 3
- Ages 2-5 years (alternative): Levocetirizine 1.25 mg daily or Desloratadine 1.25 mg daily 3
- Ages 2-11 years: Fexofenadine 30 mg twice daily 3
- Ages 6+ years: Standard adult dosing of cetirizine, loratadine, or fexofenadine 1, 2
Use liquid formulations for toddlers and young children who cannot swallow tablets. 3
Dose Escalation for Inadequate Response
If symptoms persist after 2-4 weeks of standard dosing, increase the antihistamine dose up to 4 times the standard dose (up to 2 times in toddlers when benefits outweigh risks). 2, 3 This exceeds manufacturer's licensed recommendations but is supported by guideline evidence. 2
The step-wise approach is:
- Week 0-2: Standard dose second-generation antihistamine 2, 3
- Week 2-4: If inadequate response, increase to 2x standard dose 2, 3
- Week 4+: If still inadequate, increase to 4x standard dose (in children >5 years) 2
Adjunctive Measures
Identify and eliminate aggravating factors:
- Overheating and excessive sun exposure 1, 2
- Stress 1, 2
- Hot showers and skin scrubbing 4
- Certain medications: aspirin, NSAIDs, codeine 2
- Skin drying (maintain skin hydration) 4
Apply cooling lotions (calamine or 1% menthol in aqueous cream) for symptomatic relief without systemic effects. 1
Role of Corticosteroids (Use Sparingly)
Restrict oral corticosteroids to short courses of 3 days for severe acute urticaria or angioedema affecting the mouth. 2 Do not continue beyond 3-10 days due to cumulative toxicity and questionable benefit. 2 Long-term corticosteroids should never be used except in very selected cases under specialist supervision. 2
Resistant Cases: Additional Options
For nighttime symptoms in resistant acute urticaria, add a first-generation antihistamine (hydroxyzine or chlorpheniramine) at bedtime only to help with sleep, while continuing the second-generation antihistamine during the day. 2 Never use first-generation antihistamines as first-line monotherapy due to sedation that impairs school performance. 2
For chronic spontaneous urticaria in adolescents ≥12 years who remain symptomatic despite maximized antihistamine therapy, omalizumab is indicated. 5, 6 Omalizumab has shown excellent efficacy in antihistamine-refractory pediatric cases. 6
Emergency Management
Administer intramuscular epinephrine immediately if signs of anaphylaxis develop (difficulty breathing, throat swelling, hypotension). 1, 2
Weight-Based Epinephrine Dosing:
- 15-30 kg: 0.15 mg (150 µg) epinephrine auto-injector 1, 2
- >30 kg: 0.3 mg (300 µg) epinephrine auto-injector 2
Epinephrine is life-saving for anaphylaxis or severe laryngeal angioedema. 2
Common Pitfalls to Avoid
Do not conclude treatment failure without adequate dose escalation first. 3 Many providers stop at standard dosing when up to 4x dosing is guideline-recommended. 2
Avoid using diphenhydramine or other first-generation antihistamines as primary therapy despite their historical use. 2 If diphenhydramine is used (1-2 mg/kg per dose, maximum 50 mg), 1 it should only be for nighttime adjunctive therapy, not monotherapy.
Do not perform routine laboratory investigations in chronic spontaneous urticaria unless clinical features suggest autoimmune disease, thyroid disorder, or other systemic conditions. 4 History-guided testing is more cost-effective. 4
Ensure daily dosing, not "as needed" administration of antihistamines for optimal control. 7
Prognosis and Parent Education
Reassure parents that approximately 50% of children with acute urticaria presenting with wheals alone will be clear by 6 months. 2 Chronic urticaria in children has a high resolution rate within two years and generally responds better to antihistamines than in adults. 6