SYMPTOM

Increased thirst and urination

Owners may observe increased thirst and urination in their pet.

Various conditions

This symptom can occur in multiple conditions and warrants further assessment.

Why timing matters

Early observation

Early recognition allows prompt assessment and intervention if needed.

Later presentation

Persistent or worsening signs may indicate progression requiring attention.

The significance of this symptom depends on its context, duration, and associated findings.

Conditions commonly associated

Leptospirosis

Kidney damage affects concentrating ability, leading to changes in water consumption and urination patterns.

Diabetes Mellitus in Dogs

In diabetes mellitus, the body cannot move glucose from the bloodstream into cells effectively, causing blood glucose to rise. The kidneys respond by filtering excess glucose into the urine, drawing water with it and prompting the dog to urinate more frequently and drink more to compensate for the fluid loss.

Diabetes Mellitus in Cats

Diabetes mellitus in cats causes elevated blood glucose that exceeds the kidney's capacity to reabsorb it, leading to glucose spillage into the urine. This osmotic effect draws water into the urine, increasing urination volume and triggering compensatory thirst.

Cushings Disease in Dogs

Excess cortisol in Cushing's disease interferes with antidiuretic hormone, reducing the kidney's ability to concentrate urine. This causes large volumes of dilute urine to be produced, and affected dogs typically drink substantially more water to maintain hydration.

Chronic Kidney Disease in Dogs

As kidney function declines in chronic kidney disease, the kidneys lose their ability to concentrate urine efficiently, producing larger volumes of dilute urine. Dogs compensate by drinking more water, and this pattern of increased thirst and urination often develops gradually over months.

Chronic Kidney Disease in Cats

Chronic kidney disease in cats impairs the kidneys' concentrating ability, causing them to produce more dilute urine in larger volumes. Affected cats tend to drink more to offset the fluid loss, though this compensation may not always keep pace with progressive disease.

When to explore further

When the symptom is persistent or worsening

When other signs are present alongside

When daily activities or quality of life are affected

When there is uncertainty about the cause

Noting when this symptom occurs, any triggers, and how it changes over time can provide useful information for veterinary discussions.

Last reviewed: 24 April 2026 · Dr Alastair Greenway MRCVS