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Clinical Symptom🐕 Dogs🐈 Catsurinaryendocrine

Polyuria

🗣️ Pronounced:pol-ee-YOOR-ee-uh
In One Sentence (Plain English)

The production and excretion of an abnormally large volume of urine.

Editorial Status: Verified from peer-reviewed veterinary sources (v1.0)
Updated: 2026-01-15

💬 In Plain English

Polyuria means producing an unusually large volume of urine. It is different from pollakiuria (straining to produce tiny frequent drops during a bladder infection). In polyuria, the kidneys cannot hold onto water, so the pet produces massive, pale, watery puddles or large, heavy clumps in the litter box. House-trained dogs may suddenly have large accidents indoors overnight or wake owners repeatedly to go outside.

🔬 Clinical & Technical Depth

For Vets & Technicians

Formal Clinical Definition

Urine output exceeding normal physiologic thresholds (>50 mL/kg/day in canines and felines), distinct from pollakiuria (increased frequency of small-volume micturition) or urinary incontinence (involuntary leakage).

Why Veterinarians Use It

Veterinarians assess polyuria through urine specific gravity (USG) on a refractometer to determine if urine is inappropriately dilute (hyposthenuric or isosthenuric).

Clinical Context Encountered

Frequently reported alongside polydipsia (as "PU/PD") during investigations into endocrine, renal, or hepatic disease.

Clinical Reference Guide (Clinical Symptom)

Urgency Level

🚨 Red Flag Warnings (When to Contact an Emergency Vet)
  • •If a previously polyuric animal suddenly stops producing urine entirely (anuria), this is a critical emergency requiring immediate veterinary attention.

❓ Questions to Ask Your Veterinarian

Take these actionable questions with you to your next clinic visit or appointment:

  • 1Is my pet producing large volumes of dilute urine (polyuria) or straining to produce frequent tiny amounts (pollakiuria)?
  • 2What was the exact Urine Specific Gravity (USG) number on the urinalysis?
  • 3Is there glucose or protein spilling into the urine?
  • 4Should a first-morning urine sample be collected for testing?

Academic & Clinical References