Polydipsia Polydipsia Polydipsia is excessive thirst or excess drinking. The word derives from the Greek () "very thirsty", which is derived from (, "much, many") + (, "thirst"). Polydipsia is a nonspecific symptom in various medical disorders. It also occurs as an abnormal behaviour in some non-human animals, such as in birds. This symptom is characteristically found in diabetics, often as one of the initial symptoms, and in those who fail to take their anti-diabetic medications or whose condition is poorly controlled. It can also be caused by a change in the osmolality of the extracellular fluids of the body, hypokalemia,
Polydipsia in birds chickens (broilers), subjected routinely to chronic food restriction, show increased drinking after a single daily meal along with other oral stereotypies. Expression of these activities is correlated positively with the level of restriction imposed, and is thought to be controlled mainly by central dopaminergic mechanisms. Under experimental conditions where birds receive reinforcements on a strict schedule, for example receiving one pellet of food each minute often indicated by a tone or other stimulus, the birds may develop polydipsia. Under these conditions it is called schedule induced polydipsia or sometimes, adjunctive drinking. Some strains of hens are polydipsic, drinking almost twice