When a cat stops eating, and why it is urgent sooner than you think

It's easy to assume a cat that turns up its nose is simply being a cat, and to give it a day or two to come round.

With cats that assumption is the dangerous one, because a cat not eating isn't on the same timescale as a dog skipping breakfast.

A cat's clock runs faster

When a cat stops taking in food, its body begins moving stored fat to the liver for energy, and a cat's liver handles that flood poorly.

In an animal that was carrying extra weight the process can overwhelm the organ within days, a serious condition your vet will recognise and treat but which is far easier to prevent than to reverse. This isn't a rare worst case; it's the reason vets treat feline appetite loss with urgency.

The cruel part is the loop it creates. A cat that feels sick stops eating, the liver becomes overloaded, the overload makes the cat feel sicker, and it eats less still. Once that has started, getting the cat eating again is the treatment as much as anything else — which is why the useful moment is the one before the loop closes, not after.

Weight makes it worse rather than better, which surprises people. A plump cat has more fat to mobilise and is at higher risk than a lean one, so 'it can afford to miss a few meals' is exactly the wrong instinct.

How long is too long

A cat that eats nothing for a day, or that eats markedly less for a few days running, has crossed from fussy into worth-a-call.

Bring the call forward if the cat is also hiding, drooling, vomiting, or visibly losing weight. There's no home remedy to reach for first here — the point of acting early is that early is when it's simplest to fix.

Kittens have far less margin again: a kitten that isn't eating is a same-day call, because it has almost no reserves and can become hypoglycaemic within hours. An elderly cat, a diabetic cat or one already being treated for something else is in the same bracket.

Noticing it at all, which is the harder problem

In a one-cat household this is easy. In a house with two or three, or with a cat that also goes outdoors, appetite loss can run for days before anyone spots it.

So it's worth knowing what your cat's normal actually is. Roughly how much it eats a day, whether it clears the bowl or grazes, and what time it asks. Feeding cats separately — even just in different rooms — turns a vague impression into a fact, and a bowl that's been quietly emptied by the other cat is the commonest way a problem goes unnoticed.

Weight is the backstop. A cat can lose a surprising amount under a long coat before it looks thin, so a hand along the spine and ribs once a week, or a monthly weigh on kitchen scales with a carrier, catches what the eye misses. Any loss you can measure is worth mentioning.

Plenty of causes, one next step

Appetite loss sits on top of almost anything — dental pain, nausea, stress from a change at home, or a genuine illness — and the range of possibilities is exactly why guessing is the wrong move.

A cat off its food is a signal to have looked at, not a puzzle to solve at home, and the vet is the one who can tell a sulk from a symptom.

A few causes are worth knowing about because they're common and easily missed. Dental disease, especially the painful tooth resorption cats get, makes eating hurt — a cat that approaches the bowl, eats a little and walks away, or chews on one side, or drops food, is often in pain rather than uninterested. Kidney disease, hyperthyroidism and diabetes all show up here and all reward being caught early. So does a swallowed object, particularly in a cat that's also vomiting.

Stress is a real cause and not a lesser one. A house move, a new baby, a new cat next door using the flap, building work, or a changed feeding place can all put a cat off — but stress is a diagnosis to reach after a vet has excluded the rest, not before.

Things that are worth trying while you're arranging the appointment

None of this replaces the call, and none of it is a reason to delay one. But a few of them help, and a couple genuinely matter.

Warm the food slightly, to about body temperature, which lifts the smell — smell drives feline appetite far more than taste, and a cat with a blocked nose from a virus often simply can't find the food appetising. Offer something strong-smelling it likes. Put the bowl somewhere quiet, away from the tray and away from the other cat, and use a wide shallow dish, since some cats dislike their whiskers touching the sides.

Don't starve a cat into eating. The old idea of leaving it until it gives in is genuinely dangerous in this species. Equally, don't change to a brand-new food during an illness if you can help it — a cat that feels sick while eating something develops a lasting aversion to it, and you'll want that food available later.

And never give human medicine. Paracetamol is lethal to cats in very small doses, and anti-nausea and appetite-stimulant drugs for cats exist and are prescribed for exactly this — which is one more reason the vet is the shortcut rather than the last resort.

What the vet will likely do

Knowing roughly what happens next makes the call easier to make.

Expect an examination including the mouth, a check of weight against the last recorded one, and usually blood and urine tests, since the common causes are diagnosed there rather than by looking. Treatment often starts before the cause is confirmed: fluids for dehydration, something for nausea, pain relief if the mouth is sore, and an appetite stimulant.

If the cat still won't eat, a feeding tube is sometimes recommended, and it's worth knowing that this sounds far worse than it is. A narrow tube placed under sedation lets you feed and medicate the cat at home without a fight, it's usually temporary, and for a cat with a fatty liver it's frequently the thing that turns the case around. Owners who dread it almost always report afterwards that it was the easiest part.