Urticaria (Wheals): Definition, Triggers, and Treatment

A wheal (or hive) is a transient, raised, erythematous, pruritic skin lesion caused by dermal edema from mast-cell mediator release (histamine).

Urticaria is the clinical condition characterized by recurrent wheals.

Triggers

• Allergic (food, drugs, insect venom)
• Physical (pressure, cold, heat, vibration, sunlight)
• Infections, autoimmune, idiopathic

Management

• Second-gen H1 antihistamines (cetirizine, loratadine, fexofenadine)
• Avoid triggers
• Short-course oral steroids for flares
• Omalizumab (anti-IgE) for chronic spontaneous urticaria

Angioedema (deep swelling) may accompany urticaria; if airway involved → emergency.