We’ve brought this topic up in other articles, but it’s something that we’ve seen many patients bring their cat in with a urinary tract infection for. We’ve talked about the possible actions to take if your cat does not drink enough water as well as how to avoid and treat dehydration in cats. A less common but still dangerous situation occurs when a cat starts to drink more water, but this additional drinking goes unnoticed by the cat’s owner. Do you understand the implications of your cat drinking a lot of water?

Do you think your cat drinks too much water? In this article, you will find possible explanations for why this happens. We also want to encourage all cat lovers to pay attention to their cats’ water intake habits. Especially if you have an older cat.
Table of Contents
- My cat is drinking a lot of water, should i be concerned?
- How do you know if your cat is drinking too much water?
- How much water should a cat drink per day?
- What should you do if your cat is drinking excessively?
My cat is drinking a lot of water, should I be concerned?
IMPORTANT: If you notice your cat drinking more water than usual, please visit your veterinarian as soon as possible.
In our field of veterinary medicine, drinking excessive amounts of fresh water is known as polydipsia. There is a link between polydipsia and numerous other diseases. Some of the most common are:
- Diabetes. Excessive thirst is one of the early signs of diabetes in cats. This condition is usually accompanied by sudden weight loss which is soon replaced by weight gain. It’s a very specific pattern. Even if other diabetes symptoms such as excessive urination and increased appetite do not present, please make a veterinarian visit immediately.
- Renal Failure. Your cats kidneys are part of their renal system which filters out the toxins in their bloodstream and the production of urine. Renal failure is when the kidneys no longer perform these functions which cause serious medical concerns. Symptoms of kidney disease include defecating and vomiting blood, lethargy, anorexia, and a few more. Other signs of kidney failure that may be present are diarrhea and vomiting.
- Hyperthyroidism. This is very common in cats. In fact, hyperthyroidism is one of the most common diseases in older cats. Additional signs to look for are weight loss, increased appetite, vomiting, diarrhea, poor body condition, and an enlarged thyroid gland.
There may be other cat health conditions related to increased thirst in cats and in dogs, too. But for the purposes of this article we want to focus on excessive thirst. The most important point to note is this: if your cat drinks too much, take him or her to your veterinarian immediately.
Thankfully, any of the diseases mentioned above can be efficiently managed or treated if they are diagnosed early.
How do you know if your cat is drinking too much water?

Next comes the question of whether your beloved cat is drinking water too much. How do you know if your cat’s water intake is too much?
First, the most important thing you have to do is monitor how much water your cat drinks. Don’t just replace and add water to your cat’s water bowl. You’ll want to measure how much water the bowl contains and pay attention to how much it reduces during the day. NOTE: If where you live has low humidity and/or has dry air from constant air conditioning, you should keep in mind that some of the water, maybe even a large amount may be lost to evaporation.
But how much water should a cat drink, and how much is too much? “The 5-minute veterinary consult” states that polydipsia is the greater than normal consumption of water. Normal consumption is defined as more than 45 milliliters per kilogram or 4 ounces per 5 pounds of lean body weight. NOTE: This also includes water the cat receives in food.
Example: If your cat weighs 10 pounds (an average body), their daily water need is 8 fluid ounces per day. As mentioned before, this also includes water that your cat receives in food. Most dry food contains no more than 10% moisture while canned cat food diets may consist of more than 80% water. What this means is that your cat’s diet can significantly affect how much he or she should drink.
How much water should a cat drink per day?

Here are the approximate amounts of water provided by daily amounts of dry and wet food:
- 2 ounces of dry food provides 1/5 of an ounce of water. This means that our example cat of 10 pounds must drink an additional almost 8 ounces of water. That is almost a full cup.
- The average 5 ounce can of wet food provides 4-5 ounces of water. Therefore our fictitious cat of 10 pounds should drink only 3 ounces of water per day. That is slightly more than 2 tablespoons, which is very, very little.
What should you do if your cat is drinking excessively?
Please don’t lose yourself in calculations. It is best if you can look after your cat’s water consumption habits and other behaviors over the long run. That way you can quickly notice and be on alert if things begin to change. You can learn more about your cat’s water needs here.
The best advice we offer to our patients is this. In case you notice that your cat drinking a lot of water, more so than usual lately, please visit your veterinarian. Note any other changes in your cats behavior such as increased urination, increased appetite, digestive problems like diarrhea, weight loss etc. Make sure you bring these and your cats drinking habits to your veterinarians attention. Early diagnosis of any disease will get you many steps ahead of the starting line when you need to take actions to ensure your cat stays healthy. The same rule goes for your dog if you have one.
Now that you know how much water your cat should drink per day and the potential health concerns for a cat drinking a lot of water, you can watch for any developing problems and keep your cat healthy.
Then you will be happy and your cat will be happy. And keeping your Pet happy is what we all want.