Cat Dehydration - Causes, Symptoms & Treatment | Cat Health Collection

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Cat World > Cat Health > Cat Dehydration - Causes, Symptoms & Treatment

Cat Dehydration - Causes, Symptoms & Treatment

What causes dehydration in cats?   How to check for signs of dehydration   Symptoms of dehydration   Diagnosing the cause of dehydration   Treating dehydration   Avoiding dehydration   Getting more fluids into your cat

dehydration in cats

Also known as hypohydration, dehydration is a serious and potentially life-threatening condition which is defined as excessive loss of water and electrolytes (minerals such as sodium, chloride, and potassium) from the body.

Most animals are made up of around 60% water. When the water ratio falls 5% below normal, cats will start to show signs of dehydration.

Dehydration is usually a symptom of an underlying disease.

What are the causes of dehydration in cats?

Dehydration can develop due to decreased water intake or increased output (urine, vomiting, diarrhea). Dehydration  requires veterinary attention immediately. Failure to do so may result in death.

  • Sickness - A sick cat may go off his food and water and therefore not receive enough fluids and become dehydrated.

  • Increased urination - Medical conditions such as diabetes and kidney disease in which the cat urinates more often, leading to excess fluid loss.

  • Vomiting and or diarrhea.

  • Blood loss.

  • Shock.

  • Fever.

  • Heatstroke.

  • Lack of available, fresh drinking water.

What are the signs of dehydration in cats?

Dehydration has three classes:

  • Mild dehydration: up to 5%
    Moderate dehydration: 5 - 10%
    Severe dehydration: 10% or more

Signs of dehydration include:

  • Sunken eyes.

  • Dry, tacky gums.

  • Poor skin elasticity.

  • Lethargy.

  • Increased heart rate.

  • Poor capillary refill time.

  • Loss of appetite.

  • Increased or decreased water intake.

  • Constipation. Water is reabsorbed from the colon and if the cat is dehydrated, the body will try to conserve water by removing additional water from the stool.

How to check for dehydration in cats:

Skin turgor test: To check for dehydration grasp some skin at the scruff of the neck and gently pull it up to form a tent. In the hydrated cat, the skin will spring back immediately. In a dehydrated cat, the skin will be slower to retract. The more severe the dehydration the slower the skin will take to retract. The skin will remain in the tent shape in a severely dehydrated cat. This requires immediate veterinary attention.


Capillary refill time: This helps you to test your cat's blood circulation and can indicate dehydration, heart failure or shock. To test capillary refill time life your cat's upper lip and press the flat of your finger against the gum tissue. Remove the pressure and you will see a white mark on the gum where your finger was placed. Using a watch with a second hand, time how long it takes for the pink colour to return to the white spot.

  • 1-2 seconds is normal
  • 2-4 seconds is moderate to poor
  • > more than 4 seconds is an emergency
  • < less than 1 second is an emergency


How is dehydration in cats diagnosed?

Diagnosis of dehydration is relatively easy to diagnose based on symptoms and performing the skin turgor test. However, your veterinarian may wish to determine what has caused your cat to become dehydrated and perform the following tests:

  • Complete blood count, biochemical profile and urinalysis to check electrolyte levels and kidney function.

  • Additional tests such to further investigate kidney and liver function as well as checking for diabetes.

How is dehydration in cats treated?

Finding and treating the underlying cause are essential.

In addition, medications may be prescribed to treat vomiting and dehydration is reversed by giving fluids either intravenously or subcutaneously. Intravenous fluids will need to be done at your veterinarian's surgery.

In some cases, you may be asked to give your cat fluids subcutaneously at home. This is a relatively straightforward procedure. You will be provided with needles and syringes as well as fluids. To give fluids, you lift up the loose skin at the back of the neck insert the needle under the skin and slowly administer the fluids. Your veterinarian will be able to show you how to do this. It is useful to be able to administer fluids to a cat who has an underlying medical condition such as diabetes.

How to avoid dehydration in cats:

  • Ensure there is a constant supply of fresh, clean drinking water available at all times.

  • Provide your cat with a cool, sheltered area if it has access to the outdoors.

  • If your cat is sick, monitor it closely for signs of dehydration.

  • Seek veterinary attention if your cat has vomiting or diarrhea.

  • Seek immediate veterinary attention if your cat displays signs of increased thirst or urination.

Getting more fluids into your cat:

Some cats can be fussy when it comes to water, if you need to get more fluids into him you can try the following:

  • Feed him canned or raw food instead of dry. Our cats are descendents of desert dwelling animals who obtained most of their water via their food. Dry food only contains 10% water, compared to 70% of canned or raw. Many cats don't make up the shortfall.

  • If he is reluctant to eat, try feeding him strong smelling foods such as tuna. Warm it slightly in the microwave which can make it smell stronger.

  • Make sure you change your cat's water at least once a day. If you have multiple cats, think about adding additional water bowls.

  • Some cats prefer running water. Consider buying a cat water fountain.

  • Add some tuna juice to his water to make it more appealing.

For more information on how to get cats to drink more water, read here.

Also see:

Cat symptoms  



Cat Dehydration - Causes, Symptoms & Treatment | Cat Health Collection
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Cat Dehydration - Causes, Symptoms & Treatment | Cat Health Collection