Chronic urticaria. Possible causes, suggested treatment alternatives.

Chronic urticaria is a relatively common disease with no known etiology. It does not appear to be a classic allergic reaction, and whether it has an immunologic component is not known. The diagnosis is one of exclusion: In particular, underlying disease, drug reaction, and food allergy must be ruled out. Treatment aims at relief of symptoms rather than suppression of the urticaria, and consists mainly of use of antihistamines supplemented with corticosteroids when necessary. The side effects of antihistamines are minor, and the dosage of corticosteroid used and length of time it is given are small enough to avoid major side effects.