Pruritic, edematous, pink-to-red plaques (wheals) appear suddenly and resolve completely within 24 hours, with the total episode lasting less than six weeks.
Recurrent, pruritic, edematous plaques appear spontaneously on a near-daily basis for a duration of more than six weeks without an identifiable cause.
The daily or episodic appearance of pruritic, edematous plaques persists for a duration longer than six weeks.
An edematous plaque and flare reaction develops rapidly and is confined to the site of direct skin contact with an eliciting substance.
Widespread urticarial plaques erupt in a clear temporal relationship to the administration of a new medication.
Intensely pruritic urticarial papules and plaques characteristically first arise within abdominal striae during the third trimester of pregnancy.
An urticarial plaque develops at the site of an insect sting or contact with a stinging plant due to direct mast cell degranulation.
