Updated September 30, 2026. Fact-checked against veterinary sources; review by a licensed veterinarian is in progress. See our editorial policy.
Quick answer: Early kidney disease in dogs is easy to miss. The first signs are usually drinking more water and urinating more, sometimes with accidents or needing to go out at night. Later signs include weight loss, a pickier appetite, vomiting, and bad breath. Many dogs have lost a large share of kidney function before any signs appear, so routine blood and urine tests, especially in older dogs, are the best way to catch it early.
Early signs
- Drinking more water
- Urinating more, with larger puddles or accidents
- Needing to go out at night
- Pale, dilute urine
- Slight weight loss
- Less interest in food
Later signs
- Vomiting or nausea (lip licking, drooling)
- Bad breath with an ammonia smell
- Mouth ulcers
- Lethargy and weakness
- Pale gums from anemia
- Poor coat and muscle loss
Other causes of drinking and urinating more
Diabetes, Cushing’s disease, liver disease, urinary infections, pyometra in unspayed females, and some medications like steroids also cause increased thirst. Testing tells them apart.
Tests that catch kidney disease early
- Creatinine and SDMA: blood tests of kidney function. SDMA can rise earlier than creatinine.
- Urine specific gravity: dilute urine can be an early clue.
- Urine protein:creatinine ratio: protein in the urine can signal kidney damage.
- Blood pressure
- Imaging to look at kidney size and structure
Many vets recommend yearly blood and urine tests for adult dogs and every 6 months for seniors.
Why early detection matters
- A renal diet started at the right stage reduces kidney crises and extends life.
- Treating high blood pressure and urine protein can slow damage.
- Some causes, such as infections or stones, are treatable.
- Avoiding drugs that stress the kidneys becomes possible.
Acute kidney injury: an emergency
Sudden kidney failure can follow toxins such as grapes, raisins, antifreeze, lilies (in cats), NSAIDs, or infections like leptospirosis. Signs include vomiting, not eating, lethargy, and producing little or no urine. If you suspect a toxin, call your vet or a pet poison hotline right away.
What to do if you notice signs
- Book a vet visit and bring a fresh urine sample if you can.
- Note how much your dog drinks in a day.
- Don’t restrict water.
Frequently asked questions
At what age do dogs get kidney disease?
It’s most common in older dogs but can occur at any age, including inherited forms in young dogs.
Can early kidney disease be reversed?
Chronic kidney damage can’t be reversed, but early treatment can slow it significantly.
Is increased thirst always serious?
Not always, but it’s worth checking. Hot weather and exercise increase thirst normally.
Learn more: kidney disease in senior dogs and the best diet for dogs with kidney disease.
Sources
- International Renal Interest Society (IRIS): Staging of CKD
- Merck Veterinary Manual: Chronic kidney disease in small animals
- AAHA Senior Care Guidelines for Dogs and Cats. 2023
- ASPCA Animal Poison Control Center: Grapes, raisins, and antifreeze
This article is for general education and is not a substitute for care from your own veterinarian. Learn about The Pet Vet and our editorial policy.