Cats are remarkably adept at masking illness, often causing physical issues to go undetected until they are well advanced. However, there is one place where a cat cannot hide the state of its health: the litter tray. Changes in the frequency, timing, or volume of elimination, the nature of the waste, and the cat’s behavior during the process can all serve as early indicators of common health problems. If you use ‘clumping litter’ (which forms solid clumps upon contact with waste), these signs become easily observable and can be assessed at an early stage.
The information provided below is not a medical diagnosis but rather a guide to help you stay vigilant. The key lies in understanding your cat’s normal behavior and condition, recognizing any deviations or changes, and distinguishing between issues that can wait until the next scheduled check-up and those that require immediate veterinary attention.
Every cat has a normal. Most adult cats urinate somewhere around two to four times a day and open their bowels once or twice, but the range across healthy cats is wide, which is why the number that matters isn’t the textbook one; it’s yours.
Spend one ordinary week noticing, while you scoop, roughly how many clumps appear daily and roughly what size they run. That’s it. That baseline turns every future scoop into a ten-second health check, because you’ll register “more than usual” or “smaller than usual” without trying.
Daily scooping makes this automatic, which is one more argument for the habit beyond the obvious ones covered in how often to change cat litter.
A cat suddenly producing noticeably more urine, more clumps, larger clumps, a tray saturating faster, has usually started drinking more, and increased thirst with increased urination is a pattern vets take seriously. It’s associated with several common and very manageable conditions, particularly in middle-aged and older cats, including kidney disease, diabetes and thyroid problems. Caught early, all of these have far better stories than caught late.
What to do: confirm it’s real over a few days (a heatwave or a switch toward dry food can nudge drinking too), then book a routine vet appointment and say exactly what you’ve observed: “roughly twice the usual clumps for the past week” is genuinely useful clinical information.
The opposite signal carries more urgency. Lots of tiny clumps, repeated tray visits producing very little, straining, crying in the tray, or excessive licking afterwards are the classic signatures of cystitis and the wider family of feline lower urinary tract problems, which are painful and need treatment rather than patience.
And one situation is an emergency: a cat, especially a male, straining and producing nothing at all may have a blocked urethra, which becomes life-threatening within hours. Same-day vet, no exceptions, even if it’s the weekend.
You’re not expected to inspect forensically; you’re expected to notice the obvious. Any pink or red tinge to urine or clumps warrants a vet call, and it’s easier to spot on lighter-coloured litters than dark ones. A sudden, dramatically stronger ammonia smell from the same routine can reflect more concentrated urine and is worth mentioning to the vet, especially alongside other changes; ordinary tray smell that builds between scoops is a cleaning matter, not a medical one. And the rare sweet or unusually odd-smelling tray, particularly with increased thirst, belongs in the same phone call.
Briefer, but worth the glance. Consistency matters more than perfection: formed but not rock-hard is the healthy zone, and persistent diarrhoea beyond a day or two, straining to pass hard pellets, or visible blood or mucus all earn vet conversations. Frequency changes count too, in both directions. A cat repeatedly leaving deposits uncovered right beside the tray after years of tidy burial may also be telling you something hurts when they posture, which loops back to the joint and urinary discussions above.
Sometimes the signal isn’t in the litter at all. Watch for crying or growling while toileting, frequent unproductive visits, hovering or half-squatting rather than settling, sprinting from the tray as though pursued, toileting right next to the tray, or a senior cat who has started missing the tray entirely.
Pain, urgency and negative associations all show up as tray-side behaviour before they show up anywhere a stethoscope can find them. Persistent accidents outside the tray have their own full diagnostic guide in why is my cat peeing outside the litter box, and the answer starts, as always, with a vet check.
Make it a habit and it costs nothing: roughly how many clumps today, roughly what size, any colour oddities, poo consistency at a glance, and anything unusual about how your cat used the tray. Five seconds of attention, once a day, while doing a chore you were doing anyway. Cats who can’t tell you anything are telling you everything here.
Want it on paper? The printable Tray Health Diary gives you a week-per-page grid for exactly these five checks, useful ahead of vet visits and for cat sitters.
One honest product note, because it’s relevant: this whole monitoring approach works best with a clumping litter, since discrete, countable, comparable clumps are what make changes visible. It’s one of the quieter advantages of clumping types like OliveScoop over litters where urine vanishes into the bed.
The framework holds at every age; the calibration doesn’t.
Kittens run faster in every direction: they wee more often than adults, eat little and often, and dehydrate or deteriorate quicker when something’s wrong, so a kitten’s tray changes compress the timescales above. Diarrhoea beyond a day, straining, or a kitten who abruptly stops producing anything are same-day calls, not watch-and-wait ones.
Senior cats shift in the opposite way: their baselines drift with age, which makes the weekly glance more valuable, not less, because gradual increases in urine output are precisely how the big three of later life, kidney disease, diabetes and thyroid trouble, tend to introduce themselves.
A senior whose clumps have been quietly growing for a month has already told you what the annual blood test will confirm; going in with that observation gets the right test run first. Age also adds a mobility dimension: an older cat missing the tray may be reporting joint pain rather than bladder trouble, a distinction the vet can untangle quickly when you describe both what the litter showed and how the cat moved.
Same day: straining with little or no urine (especially males), crying in the tray, any visible blood, a cat repeatedly attempting and failing, or any of these alongside lethargy, hiding or vomiting.
This week: a sustained rise or fall in clump count or size, a marked new smell, persistent soft stools, new toileting behaviour like accidents or uncovered deposits, or anything that’s simply not your cat’s normal and hasn’t self-corrected in a few days.
When in doubt, phone your practice and describe what the tray showed you; reception teams triage exactly this kind of observation every day, and no vet has ever complained that an owner knew their cat’s baseline too well.
How many times a day should a cat wee?
Typically somewhere around two to four, but healthy cats vary, which is why your own cat’s established pattern is the meaningful benchmark. A sustained change from that pattern, in either direction, is worth a vet conversation.
What do big clumps in the litter box mean?
Larger or more numerous clumps mean more urine, which usually means more drinking. Occasional variation is normal; a sustained increase is associated with conditions like kidney disease, diabetes and thyroid problems and should be checked, especially in older cats.
Can you tell if a cat has diabetes from the litter tray?
You can’t diagnose anything from a tray, but the classic early pattern of diabetes, drinking more and urinating more, shows up there first as bigger, more frequent clumps. That observation plus a vet visit and a simple test is how many cases are caught.
Why is my cat’s urine suddenly so strong-smelling?
Concentration, diet and hydration all play a role, and warm weather intensifies everything. A sudden marked change without an obvious explanation, or a strong smell alongside straining, frequency changes or accidents, is a vet-call combination rather than a cleaning problem.
