Aquagenic angioedema.

A 21-year-old man experienced persistent swelling of his lips and generalized pruritus without hives associated with swimming. Provocative testing with tap water produced transient edema and pruritus. Sweating and methacholine testing did not produce cholinergic urticaria. After several weeks, the angioedema gradually subsided, the reaction to tap water became negative, and the patient was able to swim again without reactions. Water should be added to the list of physical agents that cause angioedema as well as urticaria.