The physical urticarias. An update and review.

The physical urticarias represent a unique subgroup of chronic urticarias. Investigators from the dermatology, allergy, immunology, pharmacology, and other fields are challenged by these experimentally reproducible forms of urticaria. Clinicians are excited by these diagnosable entities among the sometimes frustrating chronic urticarias. This review is an attempt to update the reader, in a categoric manner, on the physical urticarias. The following format will be used to review each of the physical urticarias--clinical features, diagnostic tests, pathomechanism, course, and therapy.