Is it possible to have an allergy to water?
A rare condition called aquagenic urticaria is often referred to as an allergy to water. Symptoms are painful but generally not fatal. Contact with water-containing substances can bring out sore hives on the surface of the skin, cause a burning sensation and induce headaches. Because saliva contains water, the condition also hinders intimacy. Death could occur when water is swallowed if the throat swells up, blocking the airway. The root cause is unknown. One hypothesis is that H2O generates a toxic compound in the outer layers of the skin, prompting the release of histamines. There is no cure but the reactions can sometimes be controlled with antihistamines.
Answered by Michael Simpson.