Is Your Cat Drinking Enough? 3 Signs of Feline Dehydration


Dehydration occurs when a cat’s body loses more fluids than it takes in. This can happen due to illness, excessive heat, or not drinking enough water. Dehydration is dangerous for cats because their bodies contain a high percentage of water compared to humans. Cats who become moderately to severely dehydrated risk kidney damage, seizures, coma, and even death if not treated promptly.

According to Cornell University, diseases like chronic kidney disease, diabetes, vomiting, and diarrhea are some of the most common causes of dehydration in cats [1]. Petplace notes cats don’t have an innate urge to drink when thirsty, making them prone to dehydration [2]. That’s why it’s critical for cat owners to monitor their pet’s water intake and watch for signs of dehydration.

Signs of Mild Dehydration

Mild dehydration in cats can be harder to detect, but there are a few key signs to look out for. According to WebMD, some of the early signs of mild dehydration in cats include:

– Increased thirst – Your cat may start drinking more water trying to rehydrate itself.

– Dry gums – A cat’s gums should normally be moist and tacky. Dry or sticky gums can signify the beginning stages of dehydration.

– Lethargy – You may notice your cat sleeping more often and being less active as its energy starts to decline from fluid loss.

Other potential signs of mild dehydration according to PetMD include decreased appetite, constipation, and concentrated urine. If you notice any of these symptoms, monitor your cat closely and make sure fresh water is always available. Mild dehydration can progress quickly to moderate or severe levels.

Signs of Moderate Dehydration

Cats with moderate dehydration will exhibit more pronounced symptoms. According to [WebMD](, common signs of moderate dehydration include:

  • Sunken eyes – A dehydrated cat’s eyes may appear more sunken and recessed due to decreased tissue turgor.
  • Poor skin elasticity – When you pinch the skin on the back of a moderately dehydrated cat’s neck, it will be slow to snap back into place.
  • Rapid breathing – The cat may breathe more rapidly as its body tries to compensate for fluid loss.

Additional signs can include lethargy, weakness, vomiting, and cool extremities as blood flow is redirected away from the skin and extremities. According to [PetMD](, owners may also notice decreased urination. It’s important to address moderate dehydration quickly by providing fluids and contacting a veterinarian if symptoms do not improve.

Signs of Severe Dehydration

Severe dehydration in cats is a life-threatening emergency that requires immediate veterinary treatment. According to WebMD, some signs that a cat may be severely dehydrated include:

Weakness and Collapse – Severely dehydrated cats often appear extremely weak or lethargic. They may have difficulty standing or walking normally. In severe cases, cats may collapse and be unable to get up at all without assistance.

Constricted Veins – With severe fluid loss, a cat’s veins may appear constricted or collapsed when visually inspected by a vet. The veins do not refill as quickly when pressed on.

Cold Extremities – Due to poor circulation and blood flow, a severely dehydrated cat’s legs and paws may feel unusually cool or cold to the touch. The body pulls blood away from the extremities to conserve resources.

If a cat exhibits these signs, immediate veterinary assessment and treatment with intravenous fluids is needed. Severe dehydration can lead to electrolyte imbalances, poor blood flow, kidney damage, and even death if left untreated. Cat owners should contact their vet right away or visit an emergency clinic if severe dehydration is suspected.

Causes of Dehydration

There are several common causes that can lead to dehydration in cats:

Insufficient water intake – Cats that don’t drink enough water are at risk of dehydration. Some reasons a cat may not drink enough include if their water bowl isn’t easily accessible, the water doesn’t taste good to them, or they have a decreased appetite.

Vomiting – Frequent vomiting leads to fluid loss and electrolyte imbalances. Vomiting may be caused by viral infections, parasites, food allergies, eating toxic substances, kidney disease, or other gastrointestinal issues (source).

Diarrhea – Loose stools result in fluid loss and dehydration. Diarrhea can be caused by bacterial or viral infections, intestinal parasites, food allergies, inflammatory bowel disease, or other conditions (source).

Fever – Cats with a fever or high body temperature tend to breathe heavily and pant more, which leads to increased fluid loss. The underlying illness causing the fever is usually the main reason for dehydration.

Risk Factors

Certain cats are at higher risk of becoming dehydrated than others. The main risk factors include:

  • Young kittens – Kittens under 12 weeks old have an immature immune system and gastrointestinal tract, making them prone to dehydrating illnesses like diarrhea. Their small body size also means they can become dehydrated more quickly.

  • Senior cats – Older cats are at increased risk due to aging kidneys being less able to concentrate urine. Underlying chronic kidney disease is common in senior cats and predisposes them to dehydration.

  • Underlying disease – Cats with diseases like kidney disease, hyperthyroidism, diabetes mellitus, cancer and heart disease are at higher risk. These diseases can inhibit the body’s ability to maintain fluid balance.

Owners of young kittens, senior cats, and cats with chronic illnesses should be vigilant about their pet’s hydration status and contact a vet promptly at the first signs of dehydration.



If you suspect your cat is dehydrated, the vet will perform a physical exam and look for signs of dehydration. Some common diagnostic tests include:

  • Skin turgor test – the vet will pinch a fold of skin and check how quickly it returns to normal. Dehydrated skin is less elastic and returns to normal slowly.
  • Checking the gums for tackiness – dehydrated cats often have thicker saliva and tacky-feeling gums.
  • Checking for sunken eyes.
  • Blood tests – a blood chemistry panel can show increased concentration of salts and proteins due to fluid loss.

Severe dehydration can cause vital signs like temperature, heart rate and blood pressure to change. The vet will check for these abnormalities as well. They may recommend advanced imaging like ultrasound to check for issues like kidney failure that can cause dehydration (1).



The main treatment for dehydration in cats is fluid therapy to restore fluids and electrolyte balance. This is often done by administering IV fluids, but can also be done by injecting fluids under the skin (subcutaneously). Vets may give fluids at the clinic and send cats home with subcutaneous fluids that owners can administer at home. The amount and type of fluids depends on the severity of dehydration.

Electrolyte supplements may also be given to replenish important electrolytes like sodium, potassium, and chloride. These help regulate fluid levels in the body. Oral electrolyte supplements or palatable high-calorie nutritional gels containing electrolytes can help cats regain normal electrolyte balance.

If nausea and vomiting are causing the dehydration, vets may prescribe anti-nausea medication like maropitant to control nausea and prevent further vomiting episodes. This allows the cat to keep fluids down.

Severe dehydration requires hospitalization for IV fluid therapy, electrolyte supplementation, and medication until the cat is stabilized. Preventing further water loss is key to recovery.

With prompt veterinary treatment, cats can recover well from dehydration. However, severe untreated dehydration can be fatal, so it’s critical to get veterinary care for dehydrated cats.


There are a few key ways to help prevent dehydration in cats:

Provide fresh, clean water daily. Cats should always have access to fresh water. Change the water in water bowls at least once a day. Consider providing multiple water bowls around the home.

Feed a wet food diet. Canned/wet cat foods contain a high percentage of water, which can help cats stay hydrated. Aim for at least 50% of the diet coming from wet food.

Monitor water intake. Take note of how much water your cat is drinking each day. A decrease in water consumption could be an early sign of dehydration.

Make water more enticing. Try adding a water fountain, placing bowls in different locations, or adding a bit of low-sodium broth to the water.

Check their hydration status. Look for signs of dehydration like dry gums, lethargy, and skin tenting. Weigh your cat regularly to monitor any weight loss that could indicate dehydration.

Talk to your vet about supplements. Products like hydration gels and electrolyte supplements can help with hydration.

By staying vigilant about your cat’s water intake and hydration status, you can help prevent the serious effects of dehydration.

When to See a Vet

Signs of moderate to severe dehydration require immediate veterinary care. If your cat is showing signs such as lethargy, sunken eyes, dry gums, weakness, or collapsed veins on the neck, you should take them to the vet right away (Source). Left untreated, dehydration can lead to potentially fatal complications such as kidney failure, seizures, or coma. The longer a cat goes without fluids, the worse the prognosis becomes.

At the vet, tests like skin turgor, mucous membrane moisture, and bloodwork will help determine the severity of dehydration. Moderate dehydration usually requires subcutaneous or IV fluid therapy to restore hydration levels. Severe dehydration is a medical emergency requiring hospitalization for aggressive IV fluid treatment and monitoring.

Even if you are treating mild dehydration at home, contact your vet if symptoms persist more than 24 hours or seem to be getting worse. Dehydration can escalate quickly in cats, so do not delay in seeking veterinary care when signs point to moderate/severe dehydration.

Scroll to Top