Urticaria (Hives)
Raised, itchy welts from temporary leakage of fluid from small skin blood vessels.
Primary risk age: All ages.
- Urgency
- Moderate
- Typical age
- All ages.
- Body system
- Immunological & Allergic
Typical course: Acute urticaria typically fades within hours to a few days; chronic urticaria is defined as lasting more than 6 weeks.
Reviewed against AAP · CDC · WHO · NHS guidance Last reviewed 2026-06-13
1. Summary & Pathophysiology
Raised, itchy welts from temporary leakage of fluid from small skin blood vessels.
Pathophysiology (Development Path)
Release of histamine from skin mast cells makes small vessels leaky, producing the itchy raised wheals that move around and fade within hours.
Primary Causes & Etiology
Often viral infections in children; also foods, medicines, insect stings, or contact triggers. Many acute cases have no identified cause.
2. Symptom Continuum
- Early Onset Signs
Sudden itchy raised welts, pink with paler centers, that come and go.
- Progressive Phase
Welts of varying size that move location, individually lasting less than 24 hours; sometimes soft swelling of the lips or eyelids (angioedema).
- Severe Indicators
Swelling of the tongue or throat, trouble breathing, drooling, vomiting, dizziness, or collapse signal anaphylaxis — a medical emergency.
3. Clinical Verification
Clinical diagnosis from the typical fleeting welts; testing is reserved for clear trigger patterns or chronic cases.
4. Care & Elements Plan
Primary Care Treatment Plan
Remove any obvious trigger and treat itch with a non-sedating antihistamine. Anaphylaxis is treated immediately with intramuscular epinephrine.
Home Support Elements
Avoid known triggers, keep the child cool, and use cool compresses for itch. Watch closely for any breathing or swallowing difficulty.
Generic Active Ingredients (No Brands)
- Cetirizine or loratadine (non-sedating antihistamine active ingredients for itch)
- epinephrine (intramuscular active ingredient for anaphylaxis, given immediately)
- cool compresses (drug-free relief).
Lists active elements only. Never administer self-designed therapies.
5. Doctor Critical Lines
Critical Thresholds: When to See a Doctor
Call emergency services for any trouble breathing, throat or tongue swelling, repeated vomiting, or faintness. See a doctor for hives lasting more than 6 weeks, hives with joint swelling, or an unclear trigger.
6. Vaccine & Prevention
Routine Prophylaxis (Prevention)
Avoiding identified triggers prevents recurrences; many acute cases cannot be prevented.
Immunization Context
No vaccine prevents hives; children with a history of anaphylaxis should discuss vaccination safely with their clinician.
7. Timelines & Outlook
Active Timeline
Acute urticaria typically fades within hours to a few days; chronic urticaria is defined as lasting more than 6 weeks.
Expected Prognosis
Good; most acute hives resolve within days, though chronic hives can persist for months and usually settle over time.
Potential Untreated Complications
Progression to anaphylaxis when part of a severe allergic reaction; sleep disruption from itch.
More in Hypersensitivities & Atopic Responses
Emergency Anaphylaxis (Pediatric)
Acute Systemic IgE-Mediated Hypersensitivity Reaction
All pediatric ages (Infants and young children have unique symptom presentations)
Mild Allergic Rhinitis (Hay Fever)
Type I IgE-Mediated Nasal Mucosal Hypersensitivity
Preschoolers through Adolescents (Rarely diagnosed before 2 years of age)
Moderate Cow's Milk Protein Allergy (CMPA)
IgE or Non-IgE Mediated Pediatric Food Hypersensitivity
Infants (usually presenting in the first 6 months of life)