Why Is My Cat Drinking More Water Than Usual?

Why Is My Cat Drinking More Water Than Usual?

Your cat is drinking so often that you’re beginning to wonder if they’ve been running the odd marathon or two while you’re at work. The apparently unquenchable thirst has been going on for a few weeks now and you’re beginning to worry.

Plenty of cat owners will have felt the same concern. Like you, they’ll often think, “My cat drinks a lot of water. Should I worry?” 

There are often good reasons why a cat is drinking considerably more than seems normal. Find out why as we dig into the details about what could be going on.

How Much Water Is a Normal Amount to Drink?

All cats are different and will drink varying amounts depending on their lifestyle, health, and environment. It stands to reason that a cat that lives indoors in a cool house may not drink as much as an active cat who spends most of the time outside. 

Your vet can help explain to you approximately how much water your cat needs based on their diet, lifestyle, and physical health. Cats that eat only dry food are likely to drink more, for example.

Here’s a guide to working out roughly how much your cat should drink each day depending on their weight:

  • A kitten aged up to 6 months weighing around 2,5 kg: 135 ml of water
  • A medium-sized cat weighing up to 4kg: 200 ml of water
  • A big-sized cat weighing 6kg or more: 300 ml of water

Changes in Your Cat’s Behavior

Of course, It can be hard to keep an eye on your cat’s water intake. If you have concerns, you should watch for other signs that your cat is drinking substantially more than usual. Here are the 3 main ones:

  • More trips to the water bowl than usual
  • You’re refilling the water bowl more often
  • Your cat is drinking from unusual places like taps or ponds and hasn’t before

Changes in behavior can also accompany increased thirst. Look out for:

  • A change in appetite
  • Unusual instances of aggression
  • An alteration of sleeping patterns or sleeping in odd places
  • Sickness or diarrhea

If you spot any of these symptoms, it’s time to visit the vet.

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Doing Some Troubleshooting

Before drawing any hasty conclusions, take a moment to think about the cause of excessive drinking. Ask yourself these questions: 

  • Is your house extremely warm? 
  • Is your cat only eating dry food?
  • Has their drinking increased due to a hot summer?

If an environmental factor seems plausible for a change in your cat’s drinking habits, it may be sufficient to keep an eye on their general health and behavior. Keep in mind though that increased drinking may be the first sign of an underlying disease – so the safest option is a visit to the vet.

If your cat seems unwell, book them in to see the vet as soon as possible. Your vet will come up with a plan for investigation and what the possible next steps are.

If your cat has started to drink regularly from lots of unusual sources like dripping taps, ensure that everything’s all right with the water you’re leaving them to drink. Cats often avoid water bowls that aren’t super-clean.

Why Does My Cat Drink a lot of Water?

Sometimes more serious problems begin with excessive drinking. An underlying problem can cause excessive urination and a cat will drink more to compensate. 

Example reasons for an increase in thirst and urinating more than usual are:

  • Kidney disease
  • Liver disease
  • Diabetes mellitus 
  • An overactive thyroid (Hyperthyroidism)
  • Urinary tract disease
  • Compensating for losses after episodes of vomiting or diarrhea

Having Concerns Because a Cat is Older

The three of the most common causes of this in older cats are chronic kidney disease, diabetes mellitus and hyperthyroidism. Here’s an overview of each:

1. Chronic Kidney Disease

This is common in older cats although cats of any age can suffer from the disease. It happens when something goes wrong with the structure or function of one or both kidneys. 

The key functions of kidneys include:

  • Getting rid of waste products
  • Producing certain hormones and vitamins
  • Balancing electrolytes
  • Maintaining the body’s water balance

When the kidneys aren’t working properly, cats can begin to urinate more often. That can lead to them wanting to drink more. Again, simple urine and blood tests can be indicators of kidney disease. 

Chronic kidney disease is progressive. Managing it means trying to slow this progression and treat any symptoms. Apart from increased thirst, signs can include:

  • A decrease in appetite
  • Weight loss
  • Nausea, vomiting or diarrhea 

Treatment typically involves changes to a kidney-friendly diet, anti-nausea medications and antacids. It may also mean treatments for concurrent problems such as high blood pressure or anemia.

2. Diabetes Mellitus

This is a hormonal problem. Your vet will recognize it when blood sugar levels are very high and sugar spills into the urine. In humans, Type II diabetes happens when there is resistance or dysfunction of the cells in the pancreas that produce the hormone, insulin.

In cats, diabetes mellitus is most like Type II diabetes in people. Most cats that develop diabetes mellitus tend to be older than 5. It’s more common for male cats to become diabetic compared to females. Many of them will be overweight. 

Apart from increased drinking and urination, signs of diabetes in cats include increased appetite, weight loss, an abnormal hair coat and weakness in the hind legs. Your vet  can diagnose diabetes through urine and blood tests. Treatment can mean daily injections of insulin and routine monitoring by a vet.

3. Hyperthyroidism

This occurs when the thyroid glands produce excessive active thyroid hormones. It’s more typical in middle-aged to older cats. Excess thyroid hormones can increase metabolism and lead to weight loss. 

Along with excessive drinking, signs can include weight loss, an increase in appetite, hyperactivity or restlessness, diarrhea or vomiting. Again simple blood tests can help your vet to make a diagnosis. 

Treatment generally involves oral medications – but there are a few other options as well.

Talk to a Vet Right Now!

When cats drink more than normal there could be nothing to worry about, but it can be a sign that something more serious is going on. Do you still have any concerns about your cat? Then schedule a video consultation with one of our qualified vets!

We have plenty more helpful articles in our blog section. We’re also able to offer a comprehensive range of cost-effective pet insurance products.

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