What are urticaria and CSU

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Urticaria, often known as hives or nettle rash, refers to a group of 14 different conditions, all of which have an itchy, burning rash as the main symptom.

Urticaria is pretty common, affecting about one in five of the population.1 Most of the time it’s short-lived and doesn’t come back; however, 0.5–1% of people go on to develop chronic spontaneous urticaria (CSU), which can last for weeks at a time.2,3

Find out more about CSU and urticaria from Dr Pixie McKenna.

Are you a typical CSU sufferer and how long does CSU last?

Take a deeper look at the factors involved in CSU.


Chronic spontaneous urticaria

Urticaria that keeps recurring without warning is usually called chronic spontaneous urticaria or CSU.3

Unlike other forms of urticaria, which appear as result of an allergy or response to physical factors like heat or pressure, in CSU the hives appear spontaneously, without a specific trigger.3 Does your urticaria have a trigger?

CSU shouldn’t be confused with an allergy, although it may look like one.

What are the other myths about CSU?

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Unpredictable and uncomfortable

As well as being unpredictable, the itch is usually more persistent in CSU and is often accompanied by deep tissue swelling – a condition called angioedema.2 It’s therefore no surprise that CSU can have a serious impact on people's lives.

Get advice on living with urticaria.

Thankfully, there are coping strategies and treatments available to ease and even control the symptoms of CSU in some cases.


1.     Schaefer P. Am Fam Physician 2011;83(9):1078–84.
2.     Maurer M et al. Allergy 2011; 66:317–30.
3.     Zuberbier T, Maurer M. Acta Derm Venereol 2007;87(3):196–205.

Date of preparation: December 2015    XSU15-C030j

Updated: 24-11-2015