As dogs grow old, they experience many issues that manifest with both physical and behavioral changes. Some changes are subtle and gradual, while others are intense and abrupt. Sometimes knowing which changes are normal andcustom nfl football jerseys sac eastpak jordan max aura 4 bouncing putty egg penn state jersey deuce vaughn jersey best human hair wigs for black females keyvone lee jersey sac à dos eastpak yeezy boost 350 v2 hyperspace oregon football jerseys deuce vaughn jersey custom youth nfl jersey sac à dos eastpak jordan max aura 4 which require an emergency trip to the vet’s office can be tricky.

One of the changes almost every dog parent wonders is why is my old dog drinking a lot of water. Increased water intake is typical in older dogs and can be due to normal thirst or a severe and potentially life-threatening condition that warrants immediate veterinary attention.

why do old dogs drink a lot of water

This article will discuss the most common reasons why old dogs drink a lot of water. We will also explain how to know if your dog is drinking too much and when to call your vet.


You were wondering why my old dog drinks a lot of water. Well, here are some of the most common reasons why old dogs drink a lot of water.

Kidney failure

The kidneys are vital organs that play several different roles, including toxin elimination and water conservation. Kidney problems, especially chronic kidney issues, are prevalent in old dogs.

In an old dog with impaired kidney function, the kidneys cannot efficiently concentrate the urine, which is necessary to achieve adequate toxin elimination. To compensate for this decreased efficiency, they will need extra water.

Diabetes mellitus

Diabetes mellitus develops when the body does not produce adequate amounts of insulin. Insulin is a hormone critical for maintaining normal blood sugar levels. When there is a lack of insulin, the blood glucose levels increase, reaching dangerous levels.

The kidneys try to manage the situation by taking blood sugar and transferring it into the urine. Since glucose draws water, dogs with diabetes mellitus experience increased thirst and urination frequency.

Cushing’s disease

Another common reason why old dogs drink a lot of water is Cushing’s disease. Cushing’s disease is an endocrine issue that develops due to overly active adrenal glands. The condition manifests with excessive cortisol levels in the bloodstream.

Common clinical signs of Cushing’s disease include:

  • Increased thirst
  • Increased urination (frequency and amount)
  • Ravenous appetite
  • Pot-bellied appearance
  • Skin issues
  • Muscle weakness.


Dehydration is a life-threatening emergency. It can stem from many issues in senior dogs – from cognitive dysfunction syndrome that makes dogs forgetful (including about their water intake) to profuse diarrhea because of the decreased protein digestion ability.

You can check if your old dog is dehydrated by doing the skin turgor test. Just pinch your dog skin, release it, and watch how long it takes to return to normal. In well-hydrated dogs, it returns momentarily.

If your old dog is drinking a lot of water because it is dehydrated, you need to go to the vet’s office. You will have to be more observant and ensure your dog is drinking enough water in the long run.

old dogs drink a lot of water

Medication side effect

Senior dogs often receive different medications to manage their age-related health issues. Some of those medications are likely to increase the dog’s water intake.

The reason your old dog is drinking a lot of water can be some of the following drugs:

  • Anti-inflammatory drugs – prednisone (used to treat inflammatory bowel disease, asthma, and allergies)
  • Heart failure drugs – furosemide (leads to increased urine production, which triggers increased water demand)
  • Seizure medications – phenobarbital (associated with several side effects, including excessive appetite, thirst, and urination).


An old dog drinking a lot of water is a red flag that warrants immediate veterinary attention. Not every reason that makes old dogs drink a lot of water is severe. Still, extensive veterinary examinations are good, especially in seniors that can experience swift health changes and deteriorations.

Even if your old dog is not showing any changes in its usual patterns, do not forget that seniors need frequent veterinary checkups – at least twice or three times per year. If they have chronic health issues, the frequency is even more significant.


The best of knowing whether your old dog is drinking a lot of water is by measuring its water intake. Some dog parents measure their dogs’ water intakes all the time. For those who do not have this habit, measuring is good once the dog enters its senior years.

In general, d a dog needs to drink about one cup of water per 10 pounds (approximately 5 kilos) of body weight per day. Anything more than this can be considered as increased water intake.

If your dog is splashing a lot of water while drinking, measuring the exact amount of drank water can be challenging. In such cases, you should look for a deeper bowl that limits the splashing.

dog drinking water


As explained, an old dog drinking a lot of water can mean many things – from natural thirst due to strenuous activity (even regular exercise can be harsh for a senior dog) through side effects of certain medications to severe conditions that are putting the dog’s life at immediate risk.

However, you cannot determine why your old dog is drinking a lot of water on your own. For that purpose, you need the help of your trusted vet. Therefore start measuring your dog’s water intake as soon as it becomes a senior and examined by your vet as soon as you notice increased thirst and water intake.