Characteristic urticaria appears on exposed areas on a cold day. Handling of cold objects causes immediate local reaction. Swelling of the mouth and oesophagus may occur on drinking cold water. Extensive cold urticaria may be associated with systemic symptoms such as faintness, wheezing and palpitations. Syncope can occur when the patient immerses in cold water.
Wheals form on rewarming.
In some cases, cold water at 7C is more effective in bringing out the wheal. Occasionally cold urticaria is associated with circulating cryoglobulin, cold haemolysin or cryofibrinogen. Avoid swimming in cold water. Antihistamine treatment is partially effective - Cyproheptadine may be the drug of choice. Doxepin and ketotifen may also be useful.