Why Is My Cat Drinking So Much Water?

Drinking water is a natural part of living.  The most common reason why cats drink water is because they’re thirsty.  Cats are very efficient in their internal water conservation which is one of the reasons why their urine has a pungent smell to it.  A normal, healthy cat will drink between 10-30 ml/kg daily.  Cats that eat dry food may drink a little more, but we do recommend feeding cats moist food to help maintain their water consumption.  Your cat should always have access to clean, fresh water.

Polydipsia is the medical term utilized to describe increased water consumption.  If you notice your cat drinking more water it’s important to not dismiss it as it’s often the first sign that something has changed with your cat’s internal function.

Increased water consumption is a result of 3 things:

  • Compensatory – drinking more due to exercise or increased temperature; vomiting or diarrhea leading to water loss and compensatory drinking; food with increased salt leading to increased consumption.
  • Pathological – drinking more water due to excessive water loss from a medical problem. Generally more of a chronic, ongoing problem.
  • Behavioral – drinking more water due to a behavioral problem. Behavioral polydipsia is a diagnosis by exclusion meaning we have ruled out all other reasons for increased water consumption.

The three most common reasons why cats drink more water are:

  • Kidney disease – Kidney disease is the most common diagnoses ailment in older cats. The initial signs of renal disease include increased water consumption and increased urination (polydipsia, polyuria or PU/PD for short), decreased appetite, and weight loss.  While we cannot cure chronic kidney disease, there is a lot we can do to help manage it, and early diagnosis is critical.
  • Diabetes Mellitus – Cats develop diabetes similar to Type 2 diabetes in people. The initial signs of diabetes in cats are increased water consumption, increased appetite, and weight loss.  Early diagnosis is critical to prevent a medical crisis.  Diabetes is more common in overweight cats.
  • Hyperthyroidism – A common endocrine disorder in older cats hyperthyroidism leads to increased energy, increased water consumption, and a big appetite coupled with weight loss.

Any time you and your veterinarian are suspect of increased water consumption your veterinarian will want to run bloodwork and urine work to try to diagnose the reason why.  The sooner you and your veterinarian know why your cat is drinking more and urinating more the sooner a treatment plan can be created to increase the chance of a positive outcome.  If you have questions about why your cat is drinking a lot of water please contact The Vet Set team.