What exactly is cold urticaria?

Hives. Cold urticaria is the development of urticaria or hives when one is exposed to a cold environment or other cold exposure (drink, ice).
Cold Urticaria. Hives brought on by exposure to cold air or substances. Skin that has been in contact with cold develops reddish, itchy welts (hives). Swimming in cold water is the most common cause of a whole-body (systemic) reaction. Cold urticaria occurs most frequently in young adults. And it generally clears up within a few years. Treatment usually includes taking antihistamines and avoiding cold air/water.