Kidney disease in dogs

Recognise the signs

• Early CKD (often missed): increased thirst (polydipsia) and increased urination (polyuria) — PUPD is frequently the first sign
• Weight loss and muscle wasting despite reasonable appetite initially
• Reduced appetite progressing to anorexia
• Lethargy and reduced exercise tolerance
• Vomiting, especially in the morning or after eating
• Uraemic breath — a distinctive ammonia-like or metallic smell
• Mouth ulcers and pale, ulcerated gums (uraemia)
• Dull, poor-condition coat
• Anaemia (pale gums, weakness) in advanced disease
• Acute kidney injury: sudden severe vomiting, collapse, extreme lethargy, no urine production, swollen/painful abdomen

First aid steps

1. 1. Phone your vet immediately — kidney disease must be diagnosed and staged with blood tests (creatinine, urea, SDMA, phosphorus) and urine tests (urine specific gravity, protein:creatinine ratio). Do not wait to see if symptoms improve.
2. 2. Ensure your dog has constant access to fresh water — dehydration worsens kidney function rapidly.
3. 3. If you suspect your dog has eaten a toxin (grapes, raisins, antifreeze, ibuprofen, or other human medications), this is an emergency — call your vet or the Animal Poison Line (01202 509000) immediately.
4. 4. Do not give any over-the-counter pain relief — NSAIDs (ibuprofen, aspirin) and paracetamol are dangerous in dogs and especially harmful to kidneys.
5. 5. Do not restrict water intake, even if your dog is urinating excessively — water deprivation in a dog with kidney disease causes rapid deterioration.
6. 6. Note any changes in thirst, urination frequency, appetite, and weight — this history is invaluable for your vet.
7. 7. If your dog has not urinated in over 12 hours and appears uncomfortable or distended, this suggests a blockage — emergency care needed.
8. 8. Bring any medication your dog is currently taking to the vet appointment.

While transporting to the vet

• Keep your dog calm and warm — stress and cold worsen kidney perfusion.
• Allow access to water if the dog is conscious and able to drink safely.
• If toxin ingestion is suspected, call the vet en route so they can prepare to induce vomiting or begin IV fluids immediately on arrival.
• Carry your dog if weak — do not force walking.
• Have someone else drive if possible so you can monitor the dog.

When it can usually wait

• Mildly increased thirst with normal appetite and energy in an otherwise well dog — monitor and book a routine vet appointment within 3–5 days
• Very gradual, slow weight loss without other signs — warrants a check-up but not an emergency
• Known stable CKD patient with only mild, unchanged symptoms and recent normal bloodwork

Common causes

• Chronic kidney disease (CKD): age-related degeneration, long-term high blood pressure, immune-mediated glomerulonephritis, chronic infections, dental disease bacteria entering bloodstream
• Acute kidney injury (AKI): ingestion of toxins (grapes, raisins, antifreeze/ethylene glycol, NSAIDs like ibuprofen, certain antibiotics, Easter lily — though lily toxicity is mainly cats)
• Leptospirosis (bacterial infection — vaccination-preventable)
• Urinary blockage (stones, tumour) causing back-pressure on kidneys
• Severe dehydration or prolonged shock
• Pyelonephritis (kidney infection)
• Certain breeds with hereditary nephropathy (Cocker Spaniel, Bull Terrier, Shih Tzu)

What the vet will need to know

• How long has the dog been drinking more than usual?
• Any change in urination frequency, colour, or smell?
• Any vomiting — how often, and what does it look like?
• Has the dog lost weight? Over what period?
• Current medications including flea/tick/worming treatments
• Any possible access to toxins: grapes, raisins, antifreeze, human medications, garden chemicals?
• Vaccination history — especially leptospirosis
• Any family history of kidney disease (breed-specific)?
• Has the dog had bloodwork before? When, and what did it show?

Aftercare

• Feed a veterinary-prescribed renal diet — these are specifically formulated with controlled phosphorus, restricted but high-quality protein, and added omega-3 fatty acids. Do not substitute with home cooking without dietitian guidance.
• Administer phosphate binders with food as prescribed — excess phosphorus accelerates CKD progression.
• Ensure hydration — some dogs benefit from wet food, water fountains, or low-sodium broth added to water.
• Attend all follow-up blood and urine monitoring appointments — frequency depends on IRIS stage (typically every 3–6 months for stable CKD).
• Monitor blood pressure — hypertension is common in CKD and requires treatment (amlodipine typically).
• Give all medications as directed — ACE inhibitors, anti-emetics, appetite stimulants.
• Subcutaneous fluids at home may be taught by your vet team for advanced CKD dogs.
• Weigh your dog weekly at home and report unexpected changes.

Prevention

• Keep all nephrotoxic substances locked away: antifreeze, ibuprofen, grapes/raisins/sultanas, certain antibiotics.
• Ensure leptospirosis vaccination is up to date — annual L4 vaccine recommended in the UK.
• Attend annual or biannual health checks including urinalysis for dogs over 7.
• Treat dental disease promptly — chronic bacteraemia from dental infection contributes to kidney damage.
• Manage blood pressure in at-risk breeds and older dogs.
• Early SDMA testing (a sensitive early marker) at routine vet visits for senior dogs.
• Ensure adequate hydration, especially in hot weather or during illness.

Breed-specific notes

• Bull Terrier (English and Miniature): hereditary nephropathy — screening recommended before breeding.
• Cocker Spaniel: familial nephropathy described in the breed.
• Shih Tzu: renal dysplasia reported.
• Dalmatian: unique purine metabolism — urate stones can cause obstruction and AKI.
• Cavalier King Charles Spaniel: higher prevalence of protein-losing nephropathy.
• Bernese Mountain Dog: glomerulonephritis more common.

Frequently asked questions

Related topics

• Dog not eating (loss of appetite)
• Dog vomiting — when to worry
• Suspected leptospirosis in dogs