Senior Cat Kidney Health: Recognizing Polydipsia and Early CKD Checks
๐จ Check first
Thinking "my cat drinks a lot and pees a lot lately, so they must be healthy" is a dangerous misunderstanding. Passing large amounts of dilute urine leaves the body dehydrated and thirsty, so the cat gulps down water (polydipsia and polyuria). This is the most typical early sign of chronic kidney disease.
๐ The answer in 3 seconds
- Chronic kidney disease, one of the leading causes of death in cats, is frightening because it rarely shows up in standard blood test values (BUN, CRE) until about 75 percent of kidney function has been lost.
- However, signs often appear before blood tests show anything abnormal: lighter-colored urine, bigger clumps each time, and drinking more often.
- If daily water intake keeps going above about 50 mL per kg of body weight (about 200 mL (6.8 fl oz) for a 4 kg (8.8 lb) cat, a little under 1 US cup), that is one guide for considering a vet visit. Water intake also changes with the type of food (dry or wet) and the season, so do not judge by the number alone; record how it increases over time and ask your vet about an early kidney test (SDMA) and a urine specific gravity test.
๐ Flowchart
- Step 1In the morning, measure the water exactly with a measuring cup (for example, 300 mL (10 fl oz)) before pouring it into the water bowl, then measure what is left at the same time the next morning and subtract to find the exact amount your cat drank in a day.
- Step 2When you scoop the litter, check whether the urine clumps are ping-pong ball to egg size (normal) or have grown huge like a softball (polyuria).
- Step 3If you use a two-tier litter box, check whether the urine color on the pad has changed from dark yellow to a pale color that is almost as clear as water.
โญ Step-by-step fix
Step 1 ยท What you can do at home right now
In the morning, measure the water exactly with a measuring cup (for example, 300 mL (10 fl oz)) before pouring it into the water bowl, then measure what is left at the same time the next morning and subtract to find the exact amount your cat drank in a day.
Step 2
When you scoop the litter, check whether the urine clumps are ping-pong ball to egg size (normal) or have grown huge like a softball (polyuria).
Step 3
If you use a two-tier litter box, check whether the urine color on the pad has changed from dark yellow to a pale color that is almost as clear as water.
โ Never do this
- Restricting water to cut down on urination because your cat drinks a lot (absolutely not: it quickly causes severe dehydration and uremia; always let your cat drink as much as they want, whenever they want).
- Getting only a blood test, feeling relieved that it was normal, and skipping the urine test (urine specific gravity check).
๐ Make notes for the vet
Your notes save automatically on this device, so they stay even without a signal at the clinic.