CAT CARE

Why Has My Senior Cat Stopped Using the Litter Box?

Last updated: September 21, 2026 · Written by Sam, Founder

A senior cat sitting beside its litter box

In older cats, litter box problems are usually medical: arthritis, kidney disease, diabetes, UTIs or dementia. What to rule out and how to fix the box.

Short answer: When an older cat suddenly stops using the litter box, the cause is usually physical, not “bad behavior.” The 2021 AAHA/AAFP Feline Life Stage Guidelines list urinary tract disease, constipation, diabetes, kidney disease, hyperthyroidism, arthritis pain and weakness as common causes in seniors. Start with a vet visit, then make the box easier to reach and use.

When a senior cat that’s used the litter box reliably for years suddenly stops, it’s tempting to treat it as a behavior problem. In older cats, though, this change is much more often the first visible sign of a physical issue than a training lapse.

A senior cat near a low-entry litter box — A low-entry box design matters much more once arthritis is part of the picture.

Why Does This Happen More Often in Senior Cats?

Several conditions that are common after about age 10 affect litter box use directly:

Arthritis is close to universal in old cats. X-rays showed degenerative joint disease in 90% of cats over 12 in one JAVMA study, and a Dutch study of 100 cats aged 6 and up found arthritis in 61%. That study also linked arthritis to inappropriate elimination. Climbing over a rim and squatting both hurt. More on this in our guide to hidden arthritis pain in cats.
Kidney disease and diabetes increase urine volume. Cornell’s Feline Health Center says chronic kidney disease affects up to 40% of cats over 10 and 80% of cats over 15.
Urinary infections become more likely. The Merck Veterinary Manual notes that cats 10 and older are at increased risk of bacterial bladder infections, while urinary signs in young cats are usually non-infectious.
Cognitive decline can make a cat genuinely forget where the box is. It’s common: one review estimates that 28% of cats aged 11–14 develop at least one age-related behavior problem, rising to over 50% at 15 and older (Gunn-Moore et al., 2007). See signs of cat dementia.

What Medical Causes Should Be Ruled Out First?

Possible cause	Clues you might see at home	What the vet typically checks
Arthritis	Jumps less, goes right beside the box, stiff after naps	Joint exam, sometimes X-rays or a pain-relief trial
Kidney disease	Drinking more, bigger urine clumps, weight loss	Creatinine, SDMA, urine concentration, blood pressure
Diabetes	Drinking and urinating more, weight loss despite a good appetite	Blood and urine glucose, fructosamine
Hyperthyroidism	Weight loss with a big appetite, restlessness, yowling	Total T4, feeling the neck for an enlarged thyroid
Bladder infection, stones or cystitis	Small, frequent pees, blood in urine, crying while urinating	Urinalysis, urine culture, imaging
Constipation	Hard, dry stools, straining, stool left outside the box	Physical exam, sometimes X-rays
Cognitive dysfunction	Seems lost, cries at night, forgets routines	Diagnosed only after other causes are ruled out

Several of these often happen together in older cats, which is why a vet will usually run bloodwork and a urinalysis together rather than testing one idea at a time. If hyperthyroidism and kidney disease are both on the table, our comparison of hyperthyroidism vs. kidney disease in senior cats explains how vets tell them apart.

When Is It an Emergency?

A cat that strains in the box and passes little or no urine needs to be seen the same day. Cornell describes urethral obstruction as “a true medical emergency,” more common in males, and says death can follow complete blockage in less than 24 to 48 hours. Repeated trips to the box, crying, and licking the genital area are warning signs.

How Can the Litter Box Itself Be Adjusted for a Senior Cat?

Once a medical cause has been treated or ruled out, the setup is the next thing to fix:

Lower the entry. Guidelines say box edges shouldn’t be so high that a senior cat struggles to get in and out. A cut-down storage tub or a box with a low front works well.
Go bigger. AAHA/AAFP recommend a box at least 1.5 times the cat’s length from nose to tail tip, and note that most manufactured boxes are too small. Larger storage containers are an easy fix.
Put a box where the cat spends its time. Place boxes close to the cat’s core areas and avoid making it climb stairs. The general rule is one box per cat plus one extra.
Keep the litter simple. Most cats prefer unscented, clumping litter. International Cat Care suggests about 3 cm (just over an inch) of fine litter.
Clean it often. Scoop at least daily; iCatCare suggests twice a day. Wash the box with hot water rather than strong-smelling chemicals.
Help a confused cat find it. A night light near the box and keeping it in the same place help cats with cognitive decline.

Automatic boxes can suit some older cats but not others. See whether automatic litter boxes help senior cats, and how smart litter boxes can flag changes in urination. For wider changes around the house, see our home modifications for arthritic pets.

A senior cat walking carefully across a room — A change in gait or mobility is worth noticing alongside litter box changes.

What Should You Avoid?

Punishment of any kind. The AAHA/AAFP guidelines say cats should never be reprimanded for toileting in the wrong place or taken to the box as punishment.
Waiting for it to “settle down.” The same guidelines note that only 31.7% of cats with house-soiling in a 2016 study had been seen by a vet for it. The longer it goes on, the more the new spot becomes a habit.
Giving human pain relievers. If arthritis turns out to be the cause, only use medicine prescribed for your cat. Many human painkillers, including acetaminophen (paracetamol), are toxic to cats.

When Should You See a Vet?

Any new litter box problem in a senior cat is worth a vet visit, ideally within days rather than weeks. Go the same day if the cat is straining or can’t pass urine. A visit for this usually includes a physical exam, urinalysis and bloodwork. It’s also a good time to start the twice-yearly checkups the guidelines recommend for cats over 10. Treating the change as a signal to investigate, rather than a problem to punish, is the most effective way to fix it.

This article is for informational purposes only and does not replace guidance from your veterinarian.

Sources

American Animal Hospital Association / American Association of Feline Practitioners — 2021 AAHA/AAFP Feline Life Stage Guidelines, March 2021
Slingerland LI et al., The Veterinary Journal — Cross-sectional study of the prevalence and clinical features of osteoarthritis in 100 cats, 2011
Hardie EM et al., JAVMA — Radiographic evidence of degenerative joint disease in geriatric cats: 100 cases, 2002
Cornell Feline Health Center — Chronic Kidney Disease, January 2025
Cornell Feline Health Center — Feline Lower Urinary Tract Disease, October 2016
Merck Veterinary Manual — Bacterial Cystitis in Small Animals, April 2025
Gunn-Moore D et al., Journal of Small Animal Practice — Cognitive dysfunction and the neurobiology of ageing in cats, 2007
International Cat Care — Choosing a litter tray for your cat, December 2025

FAQ

Is litter box avoidance in senior cats usually medical or behavioral?

In senior cats it's medical far more often than owners assume. The 2021 AAHA/AAFP Feline Life Stage Guidelines list urinary tract disease, constipation, diabetes, kidney disease, hyperthyroidism, arthritis pain and muscle weakness as common reasons older cats stop using the box, so a vet visit is the right first step rather than treating it as a behavior problem.

Could my cat's litter box itself be the problem?

Yes, especially if the sides are tall, the box is small or it's up a flight of stairs. An arthritic senior cat may physically struggle with a box that was never an issue when younger. Guidelines recommend low edges and a box at least one and a half times the cat's length, which most store-bought boxes are not.

Why does my old cat pee or poop right next to the litter box?

Going just beside the box often means the cat is trying to use it but finds getting in, turning or squatting painful. In a study of 100 cats aged 6 and older, arthritis was found in 61% and was associated with inappropriate elimination. A lower-entry, larger box plus a vet check for joint pain usually helps.

Can kidney disease make a cat pee outside the litter box?

Yes. Chronic kidney disease makes cats produce more, weaker urine, so the box gets soaked faster and the cat may not reach it in time. Cornell's Feline Health Center says kidney disease affects up to 40% of cats over 10, so bloodwork and a urine test are standard when an older cat starts having accidents.

Is it an emergency if my cat keeps straining in the litter box?

It can be. A cat that strains and produces little or no urine may have a urethral blockage, which Cornell calls a true medical emergency, especially in male cats; death can follow within 24 to 48 hours. Go to a vet or emergency clinic right away rather than waiting to see if it passes.

Should I punish my cat for going outside the box?

No. Veterinary guidelines are explicit that cats should never be reprimanded or carried to the box as punishment. It doesn't fix the medical or physical cause, it adds stress that can make the problem worse, and it damages your bond with the cat.