Why Is My Cat Drinking a Lot of Water? Vet-Backed Guide

Should You Worry If Your Cat Drinks More Water Than Usual?

People say that cats don't need much water. Their food in the wild is largely made up of prey that is high in moisture, hence cats tend to consume less water than dogs. That's why it can be scary to see your cat consume a lot of water. Is it something to worry about, or is it merely a shift in routine?

This article discusses why cats drink extra water, whether they're unwell or their diet or habitat has changed. You're at the right position to ask, "Why is my cat drinking so much water?" . "Is it normal for my cat to suddenly drink a lot of water?"

Normal vs. Excessive | How Much Water Should a Cat Drink?

It's crucial to know what's normal before you click the panic button. A healthy adult cat needs to drink between 3.5 and 4.5 ounces (100 and 130 ml) of water every day for every 5 pounds of body weight.

Factors that influence water intake include:

• Diet (dry food vs. wet food)
• Activity level
• Age and weight
• Environmental temperature

Quick Tip:

If your cat consumes predominantly dry food, they will naturally drink more water. On the other hand, cats that eat wet food get a lot of their water from their food.

When to Be Concerned | Signs of Excessive Thirst in Cats

If you see your cat drinking a lot of water, keep an eye out for these symptoms that something might be wrong:

• Drinking from unusual places (sink, toilet, shower)
• Emptying their water bowl more frequently than usual
• Urinating more often or in larger quantities
• Restlessness or change in behavior

If these behaviors are new or escalating, it’s time to consult a veterinarian.

Factors That Affect How Much a Cat Drinks

The biggest thing that makes you thirsty is changing your diet. This is especially true if you switch your cat from dry food to wet food or the other way around. When cats eat dry food, they drink more water to make up for the fact that their diet doesn't have any water in it. Cats don't drink as much when they consume canned food, though, because it has a lot of water in it.

Cats might also drink extra water when it's hot outside. This should revert back to normal as soon as it cools off again. If it's hot or dry, you can keep your cat cool and make it less likely that they will need more water by using a humidifier.

Common Medical Reasons Your Cat Drinks a Lot of Water

If your cat suddenly starts drinking more water than normal, it could not just be because they like it more; it could be an indication of a health problem. Occasional increased thirst may not be a problem (like after playing hard or when it's hot), but drinking too much or too often, which is called polydipsia, is generally a sign of more serious health issues.

Here are the most common medical causes you should be aware of:

1. Chronic Kidney Disease (CKD)

One of the most common reasons older cats drink more water

Chronic renal disease is a long-term ailment that is most common in older cats. The kidneys don't filter waste from the blood as well, which causes too much urination and dehydration. Because of this, your cat will naturally drink extra to make up for it.

Symptoms include:

• Weight loss
• Bad breath (often ammonia-like)
• Lethargy
• Poor coat quality

Vet Tip: A blood test and a urine test can show that you have CKD. Early diagnosis and therapy, such as a renal diet and fluids, can help control the disease and make life better.

2. Diabetes Mellitus

A growing concern in overweight or middle-aged cats

When a cat's body doesn't make enough insulin or doesn't respond to it, it gets diabetes. Glucose can't get into cells without insulin, therefore it builds up in the blood instead. The extra glucose makes you urinate more, which makes you dehydrated, and your cat drinks more to make up for it.

Look out for:

• Excessive thirst and urination
• Lethargy
• Increased appetite (initially) followed by weight loss
• Sweet-smelling breath
• Unkempt fur

If you're asking “why is my cat drinking so much water and losing weight?” diabetes could be the cause.

Did You Know?
Approximately 1 in 200 cats will develop diabetes in their lifetime, and obesity is the leading risk factor.

3. Hyperthyroidism

Common in cats over 10 years old

When the thyroid makes too many hormones, it causes hyperthyroidism. These hormones control metabolism. This speeds up your cat's body functions, such needing to drink and pee.

Look for signs like:

• Sudden weight loss despite increased appetite
• Hyperactivity or restlessness
• Increased vocalization
• Vomiting or diarrhea
• Rapid heart rate

Diagnosis and Treatment:
Your vet will usually do blood tests to see how much hormone is in your body. There are other ways to treat this, such as taking medicine (such methimazole), having surgery, or radioactive iodine therapy.

4. Urinary Tract Infection (UTI) or Bladder Stones

May cause increased urination and discomfort

UTIs or feline lower urinary tract disease (FLUTD) can occasionally make cats drink more water, especially if they are straining or in discomfort when they urinate. This is more common when they are urinating a lot.

Symptoms may include:

• Straining to urinate
• Crying in the litter box
• Blood in urine
• Urinating outside the litter box

Important:
UTIs are more common in older cats or those with kidney disease or diabetes. In male cats, a urinary blockage is a life-threatening emergency.

5. Liver Disease

Affects metabolism and fluid balance

Liver problems can also make you drink more water, but this is less common. The liver helps keep blood sugar levels stable and breaks down food. If your cat's metabolism is out of whack or they're in pain, they may drink more. Cats that are older or have diabetes or kidney problems are more susceptible to have UTIs. A clogged urinary tract is a medical emergency for male cats.

Symptoms:

• Loss of appetite
• Yellowing of eyes/gums (jaundice)
• Vomiting
• Lethargy
• Weight loss

To get an accurate diagnosis of liver problems, a veterinary workup that includes blood tests and an ultrasound may be necessary.

6. Heat and Dehydration (Non-Disease Causes)

More water intake may be normal in certain scenarios

Cats don't actually have an illness, but things like heat, being very active, or a dry food (kibble) can make them naturally drink extra water.

Helpful Tip:
Make sure your cat always has access to clean, fresh water, and think about giving them wet food to help them drink more.

Read: How Often to Change Cat Litter

Non-Medical Reasons Your Cat Is Drinking More Water

Not every increase in water intake is a cause for concern. Before you jump to conclusions, think about these harmless reasons.

1. Switching from Wet to Dry Food

Wet food can have up to 80% water, while dry cat food only has about 10%. It makes reasonable that your cat is drinking more if you just changed their food.

2. Hot Weather or Increased Activity

Cats drink more when it's hot outside or after they've been playing a lot. This is perfectly natural and healthy.

3. New Water Source or Bowl Placement

Cats may drink more sometimes because their new fountain looks nicer or their bowl is easier to get to.

How to Monitor Your Cat’s Water Intake

If you're worried that your cat is drinking too much water, keeping track of how much they drink will help you figure out if it is.

Try These Methods:

• Use a Measuring Bowl: Fill your cat's water bowl with a known amount and track how much is consumed daily.
• Weigh Wet Litter: More urination = more water intake.
• Automatic Water Dispensers: Many smart fountains now track usage and offer mobile app monitoring.

When to Visit the Vet

If you notice any of the following, it's best to schedule a veterinary appointment:

• Consistently high water intake over 3–5 days
• Accompanying weight loss, vomiting, or appetite changes
• Excessive urination or inappropriate urination
• Behavioral changes or signs of discomfort

Your vet may perform:

• Bloodwork (to test kidney and liver function)
• Urinalysis (to check for diabetes or infection)
• Ultrasound or X-rays (to detect tumors or stones)

Early diagnosis can make a major difference in outcomes for diseases like kidney failure or diabetes.

Preventive Care | Keep Your Cat Healthy and Hydrated

Whether your cat drinks a little or a lot, these tips can promote good hydration and overall wellness:

Provide Fresh, Clean Water Daily

Stale or dirty water is unappealing to cats. Change it daily and clean bowls weekly.

Consider Wet Food

Adding or switching to wet food boosts hydration naturally.

Use a Cat Fountain

Cats love running water. A fountain can encourage them to drink more if they’re under-hydrated—or help you monitor intake more easily.

Clean Water Bowls Regularly

When bacteria build up, your cat may not want to drink. Use cleansers that are suitable for pets and rinse carefully.

FAQs About Cats Drinking More Water

Q1. My cat is drinking more water but seems healthy. Should I worry?

Not always. This could be because of changes in the environment, food, or way of life. But if the conduct keeps up, go to your vet to ease your worries.

Q2. Can stress cause my cat to drink more?

Yes. Changes in the environment, stress, or worry can all modify behavior, even thirst. But first, rule out any physical problems.

Q3. How can I tell if my cat is drinking too much water?

For 3 to 5 days, write down your measurements. If they drink more than the usual quantity every day (more than 1 oz per pound of body weight), it could mean that something else is wrong.

Know When to Worry and When to Watch

The amount of water your cat drinks might say a lot about their health. A little more thirst may not be bad, but you should never ignore thirst that lasts a long time or is too excessive. If you find out early on what's wrong with your cat, including their diet, the weather, or a medical issue like diabetes, kidney disease, or hyperthyroidism, you can help them get better care and live a healthier life.

If you've been asking yourself, "Why is my cat drinking so much water?" the best thing to do first is to watch, keep track, and talk to someone. Your cat is counting on you.