Now, just to be complete, here is a little bit more on the question, and a fuller response:
Can humans be allergic to water? If so, how can they survive?
Sounds crazy, but such a condition does exist. Called “Aquagenic Urticaria,” this is a poorly understood condition in which contact with water causes a hive like rash. While cold water can cause a rash due to cold-induced urticaria, with the temperature being responsible, the water itself seems to be the agent in this rare condition. Some thoughts are that trace impurities in the water, such as chlorine or fluoride, trigger the rash. Some people, though, have been reported to react to their own sweat. So it’s rare, and only water on the skin causes the problem, not drinking water, but it is a very real, and very troubling, condition.