"water would bring an acute condition to a crisis" (i.e. the "ascending douche")
If we speak of needing a cold bath of political realism, the icy shock to clear the head and get the blood pumping, we might need to work harder to find a metaphorical equivalent of the following description. (Although I remain committed to a rejection of all ascetic fantasies. Spartan measures for times of plenty, perhaps, dionysian moments for scarcer years.)
"Gräfenberg offered a menu of water treatments: head baths - patients would lie on the floor with their heads in basins of cold water; wet stomach packs; the ascending douche, spraying water up the genitals, and the wet sheet treatment, in which patients were wrapped for hours, mummylike, in wet bandages. The cold douche was the coup de grâce: icy water was discharged over patients from a height of twenty feet. These were spartan measures, but they worked well on an overfed, overdrugged, and stressed-out generation."
(description of Vincent Priessnitz's mid 19th century spa, from Porter's The Greatest Benefit to Mankind: A Medical History of Humanity)