Urticaria ( acute )

Urticaria, a common condition driven by mast cell activation, manifests as wheals, angioedema, or both. Acute urticaria has a lifetime prevalence of approximately 20%, while chronic forms, including chronic spontaneous urticaria, significantly impact quality of life and performance in daily activities such as work and school, classifying them among severe allergic diseases.

Clinical Appearance

Urticaria is identified by the abrupt onset of wheals and/or angioedema:

Wheals

• Central Swelling with Reflex Erythema: Wheals feature a central swelling of varying sizes, typically surrounded by a reflex erythema.
• Pruritus or Burning Sensation: These lesions are usually associated with itching or a burning sensation.
• Transient Nature: Wheals are fleeting, with the skin often returning to its normal state within 1–24 hours, sometimes resolving even more quickly.
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Angioedema

• Pronounced Swelling: Angioedema involves sudden, significant swelling of the lower dermis and subcutis, often extending below mucous membranes.
• Pain and Slower Resolution: Unlike wheals, angioedema may be painful rather than itchy and resolves more slowly, typically taking up to 72 hours

The hallmark of urticaria is that individual weals last less than 24 hours, although new weals can develop continuously, resulting in a persistent rash.

When the condition resolves completely within six...