Increased Thirst (Polydipsia) in Dogs

Increased thirst is a common symptom of multiple conditions. Persistent or sudden increased thirst with no known cause such as exercise, or along with other symptoms of illness, is cause for concern and warrants medical attention. Increased thirst indicates an EMERGENCY if observed with certain additional symptoms.

Gradual but noticeable increase in thirst in dogs is commonly associated with a number of conditions.

Sudden increased thirst may be one of the symptoms shown by dogs after ingesting a toxin, due to damage to the kidneys.

Increased thirst is a side-effect of some medications including but not limited to:

• Corticosteroids (e.g. prednisone/prednisolone)
• Diuretics
• Seizure medication

Some cases of excessive thirst are due to psychogenic polydipsia: an exceedingly rare behavioral disorder in which the dog drinks excessively with no physiologic cause. This is diagnosed only when all other potential causes are ruled out.

Increased thirst can be characterized as compensatory, occurring secondary to excessive urination (polyuria).

A sudden onset of polydipsia combined with other symptoms is more likely to be an emergency.

Changes in thirst can indicate a worsening of an underlying condition. If a dog showing changes in thirst has been previously diagnosed with chronic conditions such as kidney failure, liver disease, or diabetes, seek urgent veterinary care. If a dog shows increased thirst but no other notable symptoms, it is best to seek non-emergency veterinary care to rule out serious conditions.

A dog with increased thirst usually requires the following diagnostics to determine the best course of action:

• Physical examination
• Blood work
• Urinalysis Diagnostic imaging
• Therapeutic trial with desmopressin (used to treat diabetes insipidus)

Treatment varies depending on the underlying cause.

• Normal thirst
• Nausea
• Oral irritation, as occurs after eating or chewing on something that stings