idiopathic
Last reviewed 01/2018
This is the most common form of urticaria and particularly affects females with a peak incidence between 20 and 40 years of age. The onset is slow and eruptions tend to recur over periods of a few weeks, sometimes months. The majority show spontaneous remission within 6-8 months. Some however, may be prone to indefinite disease.
Some possible triggers include stress and viral infection (1)
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