Adipsia refers to a pathological absence of thirst, even when the body contains far too little water or far too much salt. It generally results from damage to the anterior hypothalamus, which is essentially Grand Central Station for neural signals related to hydration and thirst. Left untreated, adipsia is quickly fatal, as the patient simply doesn't drink anything, even though he or she is dying of thirst. Even when it's treated, it can be difficult to manage, as proper fluid balance is hard to maintain and the patient may well end up hypernatremic. Moreover, the damage to the anterior hypothalamus that causes adipsia may also affect the ability to secrete antidiuretic hormone, which in turn affects the production of urine.