Cats are stoic. They’re not as dramatic as dogs or even as us humans when something’s bothering them which is why it can be hard to tell when they’re dehydrated. Make no mistake: Dehydration can be a serious problem for a cat.

Cat Dehydration: The Basics

Dehydration is, quite simply, a situation in which the body has used up all the fluids it requires in order to carry out its basic functions. In cats, this occurs when the weather is particularly hot, after a bout of vomiting or diarrhea, through a metabolic disorder like kidney disease or diabetes, or even because of a traumatic event. Cats are particularly susceptible to becoming dehydrated because they do not have a strong “urge” to drink water like some animals do, even when their bodies need it. Because they are natural-born carnivores, they’re conditioned to get most of the moisture they consume through the food they eat. If water is not clean, easy to get to, and readily available, cats are likely to give up on the pursuit altogether. Once the effects of dehydration set in, it becomes even more difficult for them to make themselves drink.

Signs of Dehydration in Cats

Know that outdoor cats are particularly likely to become dehydrated. Cats on a diet of dry food are also more likely to dehydrate if their access to acceptable water (they’re picky!) is cut off. So, how can you actually tell if your cat is dehydrated? Here are the signs to watch for:

Check Her Skin: Fluid keeps your cat’s skin elastic and supple. If you suspect your cat may be dehydrated, pinch her gently on the extra skin between her shoulder blades to make a tent. When you let go, the skin should snap back to normal within one second or less. If it doesn’t, she’s probably thirsty.

The Eye Test: Well-hydrated cats’ eyes are distinguishable from those of a dehydrated cat. If your cat’s eyes look sunken, dull, or lack their normal focus, her body may just be lacking moisture.

Gum Check: Your cat’s gums are one of the easiest places to check her health. Her gums should always feel pink and moist, not sticky or dry. If you gently press your cat’s gum, the white spot made by your finger should return to its normal color within two seconds or less…if not, dehydration could be to blame.

Look at the Litter: Dehydrated cats are usually constipated cats. Has your cat been using the bathroom less than usual? Instead of normal poops, is the litter box full of small, hard pellet-like feces? Those signs and/or a lack of wet litter can be indicative of a hydration issue.

Other less specific symptoms like lethargy, an elevated or low heart rate, and hiding behavior can also mean your cat’s not feeling well. Remember that dehydration begets more severe dehydration, so your cat will be reluctant to seek you out once she’s feeling unwell.

What to do About a Dehydrated Cat

The sooner you recognize dehydration in your cat, the easier it should be to rectify the situation. If your cat isn’t suffering from any obvious signs of physical distress (vomiting, seizures, etc.) simply offer her clean, fresh water to drink. Remember that cats prefer not to drink anywhere near their litter boxes for fear of cross-contamination. If you think the dehydration is being caused by some other issue such as a gastrointestinal virus, call your vet immediately. In some cases dehydrated cats can only take water through medical intervention, such as an IV or subcutaneously, which means injected under the skin. Dehydration can become very serious in just a matter of hours so if you can’t get in touch with your normal vet, don’t hesitate to take your cat to an emergency veterinary clinic. 

Preventing Dehydration in Your Cat

Is dehydration a regular occurrence for your cat? Start by identifying the root cause of the issue and working backwards from there. Maybe you placed your cat’s water dish too close to her litter box? Or maybe she prefers “moving” water rather than a bowl of still water? Perhaps she just doesn’t like to drink water, so switching to canned, moisture-rich food is an easy solution? What’s most important is to talk to your vet. Regular dehydration can be symptomatic of a number of common cat ailments like kidney disease. It’s important for your vet to know your cat is having trouble staying hydrated regardless of whether or not there was an easy fix. A few simple diagnostic tests may be able to positively identify the problem.