Early Signs of Kidney Disease in Dogs — What to Watch For and What to Do

Early kidney disease in dogs often shows increased thirst/urination, weight loss and bad breath. Timely blood work and vet care can slow progression and save lives.

Is This an Emergency?

Yes — seek immediate veterinary care if any of the following are present:

• Sudden collapse, severe lethargy, unresponsiveness
• Very low or no urine production for 12+ hours
• Repeated vomiting and unable to keep water down
• Seizures, severe disorientation, or breathing difficulty
• Extremely rapid breathing or pale/blue gums

• Increased thirst and increased urination developing over days to weeks
• Gradual weight loss, decreased appetite, or bad breath
• Mild vomiting or intermittent diarrhea but still active
• Notable changes in urine appearance (cloudy, blood-tinged) or house-soiling

Why early detection matters

Kidney disease (renal disease) in dogs ranges from acute kidney injury (sudden) to chronic kidney disease (progressive). Early-stage chronic kidney disease (CKD) is often subtle. Detecting dysfunction with blood work and urine testing before clinical collapse allows interventions that slow disease progression, manage complications (like high phosphorus or anemia), and improve quality and length of life. Routine screening is especially important for older dogs and breeds at higher risk (see Prevention).

Sources such as the Merck Veterinary Manual and IRIS (International Renal Interest Society) emphasize that early biochemical changes on blood work precede severe clinical signs and give the best chance for medical management.

Common Causes (ranked by likelihood)

Early Signs to Watch For

Many early signs are non-specific. When you notice one or more of these, track them and contact your veterinarian.

• Increased thirst (polydipsia) — drinking noticeably more than usual or water bowl constantly refilled
• Increased urination (polyuria) — more trips outside, larger volumes, house-soiling
• Weight loss — especially with normal or reduced appetite
• Decreased appetite or picky eating
• Bad breath (uremic breath) — a metallic or ammonia-like odor
• Vomiting, especially intermittent
• Lethargy or less interest in play/exercise
• Dull coat and poor body condition
• Changes in urine: color, cloudiness, blood
• Mouth ulcers or drooling in advanced cases

What to Observe (before you call the vet)

Gathering clear, specific information helps your veterinarian triage and plan diagnostics.

• How long have you noticed changes? (days, weeks, months)
• Specifics on water intake: estimate daily volume if possible, or note amount relative to normal
• Urine changes: frequency, volume, color, smell, straining, blood
• Appetite and weight: weight loss amount or whether the dog is eating less
• Vomiting/diarrhea: how often and when
• Behavior: activity level, hiding, weakness
• Medications, supplements, or recent access to toxins (grapes, raisins, lilies, antifreeze, NSAIDs)
• Any recent surgery, anesthesia, or known infections
• Vaccination and leptospirosis exposure risk (outdoor, stagnant water, rodents)

Home Monitoring — what you can safely do while waiting

Do

• Keep your dog calm, dry, and comfortable
• Provide fresh water and encourage drinking (do not force-feed fluids)
• Monitor and record water intake, urine output/frequency, appetite, vomiting, and behavior changes
• Collect a urine sample in a clean container to bring to the clinic if you can do so safely
• Keep a list of medications, supplements, and potential toxin exposures

• Attempt to diagnose or treat kidney disease at home
• Give prescription or over-the-counter medications (especially NSAIDs, ACE inhibitors, aminoglycosides) without veterinary direction
• Force fluids or induce vomiting unless instructed by a veterinarian or poison control

Veterinary Diagnosis — what tests to expect

Your veterinarian will use a combination of history, physical exam, and laboratory tests.

• Blood chemistry panel (serum biochemistry): checks creatinine, blood urea nitrogen (BUN), electrolytes (potassium, sodium), phosphorus — key for kidney function.
• Complete blood count (CBC): anemia and infection markers.
• Urinalysis: specific gravity (concentrating ability), protein, blood, sediment exam for crystals or bacteria.
• Urine culture: if infection is suspected.
• SDMA (symmetric dimethylarginine): a sensitive early marker of reduced kidney function; can detect kidney disease earlier than creatinine in some cases (IRIS and veterinary studies support its use).
• Blood pressure measurement: hypertension commonly accompanies kidney disease and needs management.
• Imaging: abdominal ultrasound or X-rays to evaluate kidney size/shape, stones, or obstructions.
• Additional tests: leptospirosis titers, endocrine testing if systemic disease suspected.

Treatment Options — overview

Treatment depends on the cause (acute vs chronic), severity, and concurrent conditions.

Acute kidney injury (AKI)

• Hospitalization for intravenous fluids to restore perfusion and support kidneys
• Treatment of underlying cause (antibiotics for leptospirosis, removal of toxins, etc.)
• Monitoring of electrolytes and urine output; dialysis in severe cases (available at specialty centers)

• Dietary management: prescription renal diets lower in phosphorus and with appropriate protein and calorie content
• Phosphate binders if blood phosphorus is high
• Potassium supplementation if low
• Antihypertensive therapy if blood pressure elevated
• Treatments for anemia (iron, erythropoietin-stimulating agents in some cases)
• Management of nausea and appetite (antiemetics, appetite stimulants)
• Treatment of concurrent infections or protein-losing conditions
• Ongoing monitoring: regular bloodwork, SDMA, urinalysis, blood pressure checks

• Fluid therapy at home or in clinic for intermittent dehydration management
• Hospital-based intensive care for severe dehydration, electrolyte imbalances, or toxin exposure
• Referral to a veterinary internal medicine specialist or dialysis center for complex cases

Prevention — reduce the risk and catch disease early

• Routine wellness checks: annual or twice-yearly exams with bloodwork and urinalysis for middle-aged and older dogs
• Screening for high-risk breeds and dogs with other systemic diseases
• Protect against common toxins: keep grapes, raisins, antifreeze, certain human medications, and xylitol out of reach
• Vaccinate and manage leptospirosis risk if recommended in your area
• Maintain good hydration and avoid prolonged dehydration (e.g., after strenuous exercise or vomiting)
• Avoid long-term use of potentially nephrotoxic drugs unless monitored by your veterinarian
• Early treatment of urinary tract infections, stones, or pyelonephritis

Red Flags — Seek Emergency Care Now

• No urine production for more than 12 hours
• Collapse, severe weakness, or seizures
• Repeated vomiting and inability to keep water down
• Severe breathing difficulty or pale/blue gums
• Sudden severe abdominal pain

Key Takeaways

• Increased thirst and urination, weight loss, decreased appetite, and bad breath can be early signs of kidney disease in dogs.
• Early detection with bloodwork (including SDMA and creatinine) and urinalysis significantly improves treatment options and outcomes.
• Do not attempt to diagnose or treat kidney disease at home; collect observations and a urine sample, and contact your veterinarian promptly.
• Emergency care is required for sudden severe signs: no urine output, collapse, repeated vomiting, seizures, or severe breathing problems.
• Routine screening and avoiding toxins are the best prevention strategies.

If you suspect kidney disease in your dog, call your veterinarian and provide the observations above. Early veterinary testing and treatment can make a major difference in your dog’s comfort and longevity.

Sources: Merck Veterinary Manual; International Renal Interest Society (IRIS); ACVIM consensus guidance on renal disease in small animals.

Frequently Asked Questions