Aquagenic urticaria: Year of the Zebra 2025

Aquagenic urticaria is a rare condition in which contact with water triggers the development of itchy, hive-like skin lesions. This reaction develops regardless of the water’s temperature and source, as it can occur after contact with tap water, salt water, rain, sweat, or even tears.

Even though urticaria is a common skin condition, aquagenic urticaria is exceptionally rare, with fewer than 100 cases documented in medical literature. Unlike typical allergic reactions, aquagenic urticaria isn’t due to any component in the water itself; rather, it’s the interaction between water and the person's skin that triggers the immune response.  

Now, symptoms typically appear within 5 to 15 minutes of water exposure and include small, red, itchy wheals accompanied by a burning or stinging sensation. These lesions most often appear on areas like the neck, chest, arms, or back and usually fade within an hour.  

In people with aquagenic urticaria, everyday situations like showering, walking in the rain, sweating during exercise or in hot weather, or even crying may result in symptoms. Notably, drinking water does not trigger symptoms, as the condition is limited to skin contact. While most cases are mild, some people may experience more severe reactions like swelling or difficulty breathing after widespread water exposure.  

Because contact with water is difficult to avoid in daily life, aquagenic urticaria can lead to significant emotional distress and result in avoidance of social situations where water exposure is expected, like swimming, exercising, or being outdoors. In more severe cases, individuals may even avoid showering or washing their hands, which can further impact quality of life and self-esteem.