Water Intoxication – Hyponatremia


During the heat of the Summer, many pet owners turn to sprinklers and a trip to the lake to cool off their dog. A hidden danger of playing with water is Water Intoxication, an uncommon emergency illness to become familiar with.

What is it?

Water intoxication, also known as hyponatremia is a relatively rare but potentially fatal condition caused from ingesting excessive amounts of water. 

When your pup is playing with water, whether diving into a lake or river to retrieve a ball or biting at a hose or sprinkler for long periods of time, they can inadvertently ingest a large volume of water very quickly. This is possible if they drink an excessive amount after exercise as well. 

Excessive amounts of water will dilute their body’s electrolytes causing alarming and even fatal electrolyte imbalances. The cells in their body will begin to swell with water. If the cells in their brain swell, their central nervous system will become affected and can result in seizures, coma and even death. 

Symptoms include:

  • loss of coordination
  • lethargy
  • bloating
  • vomiting
  • glazed eyes
  • excessive salivation
  • difficulty breathing
  • seizures
  • coma

Water intoxication can progress very quickly. If your pet has been playing with water and begins to show any of the above symptoms, please contact your veterinarian immediately or take them to the closest emergency facility.


Aggressive treatment at a veterinarians office may include IV delivery of electrolytes (sodium/chloride), diuretics and medications to reduce brain swelling. These treatments are used to reduce swelling of the brain and cells, but in severe cases some patients symptoms cannot be reversed. 

How can I avoid it?

Make sure your dog takes regular breaks from the water play. If they drink their whole water bowl quickly after exercise, wait until they are settled before refilling. 

If you have any questions, please don’t hesitate to call us at 406-446-2815.