What is the initial management of acute migratory urticaria in a child?

Initial Management of Acute Migratory Urticaria in Children

Start with a non-sedating second-generation H1 antihistamine at the standard pediatric dose as first-line therapy, verifying age-specific dosing against the product label since restrictions vary for children under 12 years. 1

Immediate Clinical Assessment

The diagnosis is primarily clinical and does not require routine laboratory testing unless the history points to a specific trigger. 2, 1 Focus your history on:

• Duration of individual wheals: In ordinary acute urticaria, wheals last 2-24 hours before resolving without scarring 2, 1—this migratory pattern is typical and helps distinguish it from urticarial vasculitis (where wheals persist for days) 2
• Recent exposures: Ask specifically about common food allergens (nuts, fish, eggs, milk), recent viral infections, new medications (especially NSAIDs, codeine), and contact with latex or chemicals 1, 3
• Physical triggers: Overheating, pressure, cold exposure, or exercise may provoke or worsen urticaria 2

First-Line Pharmacologic Treatment

Antihistamine therapy:

• Second-generation H1 antihistamines are the cornerstone of treatment 2, 1, 3
• Verify the exact formulation and dose against the product data sheet because age-related restrictions vary for children under 12 years 1
• Over 40% of patients show good response to antihistamines alone 2

Short-course corticosteroids for severe cases:

• A brief course of oral corticosteroids (lower than the adult regimen of 50 mg daily for 3 days) can shorten the duration of acute episodes 1
• Restrict corticosteroids to short courses for severe acute urticaria or when antihistamines are insufficient 2, 1
• Avoid long-term corticosteroid use; reserve only for selected severe cases under specialist supervision 1

Adjunctive Symptomatic Measures

• Topical cooling agents such as calamine lotion or 1% menthol in aqueous cream provide itch relief 1
• Avoid aggravating factors: overheating, emotional stress, and alcohol exposure 1
• Avoid aspirin and NSAIDs: These may provoke mast cell degranulation and worsen urticaria 2, 1

Emergency Management for Severe Presentations

If laryngeal angioedema or anaphylaxis develops:

• Immediate intramuscular epinephrine is mandatory 1, 3
• For children weighing approximately 15-30 kg, use a fixed-dose 150 µg epinephrine autoinjector 1
• Administer a second dose if no significant improvement occurs after the first 1
• Parenteral hydrocortisone may be given as an adjunct for severe laryngeal edema, recognizing delayed therapeutic effect 1
• Consider prescribing an epinephrine autoinjector for home use when the child's history indicates risk of recurrent life-threatening attacks 1

Common Pitfalls to Avoid

• Do not perform extensive laboratory work-ups for typical acute urticaria—they are unnecessary and add no clinical value 1
• Do not routinely add H2 antihistamines: The benefit is mainly for associated dyspepsia, and supporting evidence is limited 1, 3
• Do not investigate unless history suggests a specific trigger: IgE-mediated reactions can be confirmed by skin-prick testing or specific IgE assays only when environmental allergens are suspected 2, 1
• Recognize that many cases remain idiopathic: Despite thorough evaluation, a specific cause is often not identified 2

When to Consider Further Evaluation

If wheals persist beyond 24 hours, suspect urticarial vasculitis and consider skin biopsy 2, 1. If urticaria becomes chronic (>6 weeks), screening tests including complete blood count, ESR or CRP, and thyroid autoantibodies may be warranted 1, but this is beyond the scope of acute management.