Litter boxes for cats with kidney disease

A cat with early kidney disease urinating more frequently and in larger volumes needs a litter box that keeps up — and most standard boxes simply won't. They're too small, fill up faster, and a soggy tray is one of the main reasons cats start going elsewhere. Most boxes are also too short for older cats who are slower to position themselves. The rule of thumb is a box at least 1.5 times your cat's body length — and for a senior with kidney issues, you also need enough depth to handle the extra volume without everything pooling at the surface. How big is your cat roughly, are they still mobile and able to step over a standard-height side comfortably, and are you currently seeing any avoidance — missing the box, going just outside it, or choosing other spots in the house?

That pattern — accidents just outside the box rather than elsewhere — almost always means the box itself is the problem, not the cat. He's going to it, which is good, but either it's too full by the time he arrives, too small for him to orient properly, or both. For a 4.5kg cat you're looking at needing roughly 65–70cm of usable floor space inside the box. What are you using at the moment, and how often are you scooping?

That's the issue. 45cm is too small for him at the best of times, and the cover is making it worse — covered boxes trap ammonia smell inside, and cats with any kind of discomfort or hesitation will start to associate the box with that unpleasant experience. With kidney disease increasing his output, the smell builds even faster. Twice-daily scooping is good but you need a bigger, open tray to go with it. I'd get him the Savic Senator Open Cat Litter Tray — it's 56cm long with a generous floor area and a deep rim to contain scatter and hold more volume between scoops. It's low-sided enough at the front for easy entry as he gets older, and the open design means no ammonia build-up. One change, and I'd expect the outside-the-box accidents to stop within a week.

The tray is the priority right now. For litter, an unscented clumping litter is all you need — it clumps the larger urine volumes cleanly so you can scoop properly and you're not masking smell with fragrance that some cats dislike. The Catsan Hygiene or a plain sodium bentonite clumping litter works fine. Avoid anything scented or with deodorant crystals added. If your vet hasn't already mentioned it, some cats with kidney disease also benefit from monitoring how much they're urinating — a quick weigh of the clumps over a few days can give you useful data to share at his next check-up.

Good choice. Get the largest size available — it's the 56cm one. Set it up in the same spot as the current box if you can, and leave the old one there for a few days so he can switch over at his own pace rather than being forced to adapt. Most cats move over quickly once they experience the extra space. Hope he does well with it.