If you’ve noticed your dog drinking a lot more water than usual, even if everything else seems normal, it’s worth paying attention. Increased thirst—also known as polydipsia—can be the body’s way of compensating for underlying imbalances, and early signs like this are easy to miss.
We outline the common causes of dog drinking a lot more water than usual, what you can do at home, and when to seek veterinary help.
Dog Drinking a Lot More Water Than Usual — Why It Happens
A noticeable increase in water consumption can be caused by heat, exercise, diet changes, or more concerning medical issues like diabetes, kidney disease, or hormone imbalances. Even without other symptoms, persistent increased thirst is a clue that your dog’s body might be working harder to stay balanced.
Common Causes of Dog Drinking a Lot More Water Than Usual
Normal Response to Heat or Activity
Dogs naturally drink more water after exercise or on warm days to stay hydrated.
If your dog has been more active or the weather is hotter than usual, a temporary increase in water intake may be expected.
However, if thirst remains high even after rest or in cooler conditions, it could be a sign of something else.
Diet or Salt Intake
High-sodium foods or treats—especially processed chews or table scraps—can cause dogs to drink more to balance sodium levels.
Some commercial foods also have higher salt content than necessary, especially in low-quality brands.
If your dog’s food or treat routine recently changed, review ingredients or consult your vet about alternatives.
Related: Dog drinking a lot of water and not eating (Here’s why)
Diabetes Mellitus
In diabetes, excess sugar in the bloodstream pulls water into the urine, leading to increased thirst.
This is often one of the first noticeable signs of the disease, even before appetite or weight changes appear.
Without treatment, dogs may begin losing weight, urinating more often, or becoming lethargic. Diagnosis requires blood and urine tests.
Kidney Disease
As kidney function declines, the body struggles to conserve water and concentrate urine properly.
This leads to excessive thirst and urination. It can happen gradually and without other symptoms at first.
Over time, dogs may show signs like vomiting, poor appetite, or weight loss. Early detection is key to managing the disease.
Cushing’s Disease
Cushing’s (hyperadrenocorticism) causes elevated cortisol levels, which increase water consumption and urination.
Early signs may be subtle, such as more frequent drinking or peeing, before more serious symptoms develop.
Dogs with Cushing’s may also pant excessively, develop thin skin, or gain a pot-bellied appearance. Bloodwork and hormone testing confirm the diagnosis.
Urinary Tract Infections (UTIs)
Even mild infections in the urinary tract can cause dogs to drink more, especially if they’re urinating frequently or uncomfortably.
You might not see other signs at first, but UTIs can progress quickly. Watch for accidents, straining, or changes in urine color.
UTIs are diagnosed via urinalysis and usually respond well to antibiotics.
Medication Side Effects
Corticosteroids and certain anti-seizure or heart medications may cause increased thirst as a side effect.
If your dog started a new medication recently, check with your vet to determine if the drinking is medication-related.
Never stop a prescribed medication without veterinary guidance.
What to Do If Your Dog Is Drinking More Than Usual
Measure your dog’s water intake over 24 hours. Most dogs need about 1 ounce of water per pound of body weight per day.
Make sure the water source is clean, and monitor for frequent urination, accidents, or changes in energy.
Look for subtle behavioral changes: increased restlessness, reduced stamina, or excessive licking may be tied to increased thirst.
Do not restrict access to water unless advised by your vet. Restriction can lead to dehydration and worsen underlying issues.
Document changes and bring this information to your vet for a clearer picture of what’s happening.
When to Call or Visit Your Vet
Contact your vet if your dog:
Drinks significantly more than usual for over 48 hours
Begins urinating more frequently or having accidents
Shows signs of dehydration, lethargy, or appetite changes
Has started new medications recently
Is a senior dog or has a history of kidney or endocrine issues
Your vet will likely perform bloodwork, urinalysis, and possibly diagnostic imaging to uncover underlying causes.
Early detection allows for more treatment options and better long-term outcomes.
Related
Read more: Dog Drinking a Lot of Water No Other Symptoms (Is it nothing?)
Read more: Dog Drinking a Lot of Water and Peeing a Lot (Here’s why)
Key Takeaway
An increase in water intake might seem minor, but it’s often the first clue of bigger changes in your dog’s health—especially involving the kidneys, hormones, or metabolism.
Track the behavior, check for subtle signs, and consult your vet early for peace of mind and proactive care.