Polyuria Polyuria Polyuria () is excessive or an abnormally large production or passage of urine (greater than 2.5 or 3 L over 24 hours in adults). Frequent urination is usually an accompanying symptom. Increased production and passage of urine may also be termed diuresis. Polyuria often appears in conjunction with polydipsia (increased thirst), though it is possible to have one without the other, and the latter may be a cause or an effect. Psychogenic polydipsia may lead to polyuria. The most common cause of polyuria in both adults and children is uncontrolled diabetes mellitus, which causes osmotic diuresis, when glucose levels
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