Urticaria is classified with considerations on how long symptoms have persisted plus the causes and triggers of urticaria.

In a nutshell acute urticaria are those cases where symptoms last up to a period of 6 weeks. Chronic urticaria are those cases that last longer than 6 weeks. There are some more specifics to breakdown the subtypes of urticaria  [1].

Current Classifications

Acute spontaneous urticaria

Spontaneous occurrence of wheals and/or angioedema for a total duration of fewer than 6 weeks.

Chronic Spontaneous Urticaria (CSU)

Spontaneous occurrence of wheals and/or angioedema for a total duration of 6 weeks or more.

This is synonymous with ‘chronic urticaria’ or ‘chronic idiopathic urticaria

Chronic Inducible Urticaria (CIndU)

Occurrence of wheals for a total duration of six weeks or more, which is inducible by physical factors (touch, pressure extremes). This is synonymous with ‘physical urticaria’.

Typical Presentation

Those dealing with urticaria typically present with hives alone, Angioedema alone or both. About half of cases present with hives (wheals) alone. About 10% develop angioedema as the primary symptom, and 40% present with both.

Hives

Hives present as batches of welts (wheals), which are circumscribed superficial edema (swelling) of the skin. They are usually surrounded by bright red areas with a centralized whiteness. They are usually accompanied by itchiness or a burning sensation.

Each wheal will typically come on within minutes but and last fewer than 24 hours, without any residual bruising or skin discolouration. They tend to occur in pressure prone areas like waistline, armpits, groin, but really, can affect any part of the body.