Aquagenic urticaria: a skin reaction that results from contact with water. Urticaria is the medical term for hives, a skin reaction characterized by red, raised, itchy welts on the skin. Urticaria can be related to an allergic reaction, but its cause is not determined in many cases. The skin changes can come and go, change size, and move to different locations in the body. Symptoms and signs of aquagenic urticaria are similar to ordinary hives. The exact reason why water provokes this reaction in some people is not well understood.
Rakel RE, Rakel D. "Textbook of Family Medicine." 9th edition. 2015 Saunders.