The Lethargic, Hiding Cat That Has Stopped Eating

Quick answer

A cat that is quiet, tucked away and off its food is not resting. It is the way cats show they are ill.

Cats do get fevers. What you cannot do is measure one at home in any way you should act on. Ear and forehead thermometers are unreliable in cats, a warm nose or warm ears mean nothing, and the stress of restraint raises a cat's temperature by itself.

So stop trying to take a temperature and watch the three things that actually tell you something: is the cat hiding, is it flat, and is it eating. Of those, appetite is the one with a clock attached to it.

• A cat that has not eaten for around a day is a medical priority, not a wait-and-see.
• Cats that stop eating are at risk of a liver condition that becomes an illness in its own right, and overweight cats are at the greatest risk.
• Hiding, sitting hunched, and not grooming are the earliest and most reliable signs of illness in cats.
• Never give paracetamol, ibuprofen, aspirin or any human painkiller to a cat.
• A male cat straining in the litter tray and producing nothing is an emergency within hours.

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Never give a cat human painkillers.

Paracetamol, also sold as acetaminophen, is lethal to cats in very small quantities. Cats lack the liver pathway needed to process it, and the result is damage to the red blood cells and to the liver. Affected cats show brown or muddy gums, swelling of the face and paws, laboured breathing and collapse.

Ibuprofen, aspirin, naproxen and other human anti-inflammatories are also dangerous to cats.

Never give a cat any medication that has not been prescribed for that cat. If a human painkiller has already been given, or you suspect the cat took one, go to a veterinary clinic immediately and take the packet. Treatment works far better started early, and waiting for signs to appear is what makes these cases fatal.
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Decide in 60 seconds

Why the thermometer is the wrong tool

A raised body temperature is a real and useful sign. It is simply not one you can obtain at home.

Ear thermometers designed for people do not sit correctly in a cat's angled ear canal, and forehead scanners are measuring skin over fur. Neither gives a number worth acting on.

Rectal measurement is the reliable route, and it has two problems at home. Restraining a cat that does not want to be restrained raises the temperature you are trying to measure. And a cat that has been chased around a room and pinned down has learned something about you that makes the next attempt harder, including the vet's attempt.

The nose tells you nothing. A warm, dry nose is normal in a cat that has been asleep in a sunny window. A cool, damp nose is normal too. Ear temperature varies with the room.

What you can assess at home is more useful anyway.

Is the cat where it usually is? Or has it gone somewhere new, dark and enclosed?

Can you rouse it normally? A cat that lifts its head and looks at you is different from one that does not.

Is it grooming? A coat that has gone dull, greasy or spiky in a normally fastidious cat means the cat stopped grooming days ago.

Is it eating? This is the one to measure.

What is the breathing doing at rest? Watch the chest of a sleeping cat. Fast, effortful or open-mouthed breathing is an emergency in a cat.

Gum colour. Lift the lip. Healthy gums are pink and moist. Very pale, white, blue-tinged, brick red, yellow or brown gums are all urgent.

Why a day without food is the line

This is the fact that changes how you should think about a quiet cat.

When a cat stops taking in enough calories, its body does what any body does and mobilises stored fat for energy. That fat travels to the liver to be processed.

The feline liver is comparatively poor at packaging fat back out for the rest of the body to use. So fat arrives faster than it leaves, and it accumulates inside the liver cells themselves. Liver function falls.

The cruelty of it is that it feeds itself. A cat with a failing liver feels nauseous and eats even less, which mobilises more fat, which worsens the liver.

Overweight cats are at greatest risk, because they have the largest fat stores to mobilise. A chubby, otherwise healthy cat that goes off its food after a stressful house move, a boarding stay, a new cat in the home, a diet change or any minor illness is the classic case.

Yellowing of the gums, the whites of the eyes or the pale skin inside the ears means the process is already well advanced. Do not wait for it. The signal to act on is the not-eating, not the jaundice.

This is why every part of this article comes back to appetite, and why "he will eat when he is hungry" is dangerous advice for a cat, however sensible it sounds for a dog or a child.

Measuring appetite properly

Weigh what you put down and weigh what comes back. Impressions are not evidence, and the difference is the one number a vet can use.

Put down a weighed or measured amount. Take away what is left after the meal and weigh or measure that too. Write both down with the time.

In a multi-cat home you do not know who ate. Feed separately, in different rooms, for as long as it takes to answer the question. A cat that is quietly not eating in a house where the bowl empties every day is the commonest way this gets missed.

Water matters too, but changes in drinking are harder to read and are usually a longer-term signal. Note it, but do not let normal drinking reassure you about an absent appetite.

Weigh the cat. A digital scale, weigh yourself, weigh yourself holding the cat, subtract. Do it weekly in a healthy cat and daily in a cat you are worried about. Weight loss in a cat is always significant and it is often the first hard number anyone has.

Note urination and defecation. In a litter tray you can count and see. No urine in a day is an emergency in itself.

Age changes the likely cause

The signs are similar at any age. What sits behind them is not.

Kittens. They have almost no reserve. A kitten that stops eating can become hypoglycaemic and dehydrated within hours, and a flat, cold kitten is an emergency at any hour. Common causes include the viruses that cause severe vomiting and diarrhoea, and upper respiratory infections. A blocked nose matters more than it sounds: cats will not eat food they cannot smell, so a snuffly kitten stops eating for a mechanical reason. Kittens also swallow things they should not.

Young and middle-aged adults. The classic fever case in an adult cat with outdoor access is an abscess from a bite. A cat bite punctures deep and seals over within a day, trapping bacteria under the skin, and the cat becomes flat, feverish and off its food several days after a fight nobody witnessed. Look and feel for a hot, painful swelling, often at the base of the tail, on a shoulder or on the face, sometimes with a small scab. Other causes at this age include swallowed foreign material, particularly string, and in an unspayed female a womb infection, which is a surgical emergency and often presents as a flat cat that is drinking heavily.

Male cats of any adult age. A blocked urinary tract deserves its own line, because it presents as a cat that is flat and off food and it is fatal within a day or two. Repeated trips to the tray producing nothing, straining, crying, licking at the penis, vomiting, and then collapse. Owners often think the cat is constipated. Treat it as an emergency, at once.

Senior cats. Overactive thyroid, kidney disease, diabetes, dental disease and tumours all become more common. A senior cat that has become quieter, hides more and eats less is very often in pain rather than simply old. Dental pain in particular makes cats approach the bowl, look at it and walk away, which owners read as fussiness.

At every age, a cat that stops eating for around a day carries the same liver risk on top of whatever the underlying cause is. The age changes the diagnosis, not the urgency.

Making an unwell cat more likely to eat

These are things to do while you arrange an appointment, not instead of one.

Warm the food gently to blood heat. Smell drives feline appetite, and warming lifts the aroma. Do not serve it hot.

Offer strongly scented wet food rather than dry, and offer it in a wide, shallow, clean dish.

Take away food that has been refused and offer fresh a little later. A bowl of drying food in front of a nauseous cat builds an aversion to that food.

Feed somewhere quiet, away from other cats, dogs and household traffic.

Clear a blocked nose with steam from a running shower in a closed bathroom, with the cat in the room rather than in the water, if the cat is snuffly.

Do not change the food to something new and unfamiliar during illness. Cats readily form lasting aversions to whatever they were eating when they felt sick, and that includes any new food you introduce now. Save the new food for after recovery.

Do not withhold food to make the cat hungry enough to eat. That is the specific mistake this article exists to prevent.

What the vet needs from you

Do not offer food or water on the way to the clinic if surgery or sedation is a possibility, and ask about this when you book.

What never to do

Do not give paracetamol, ibuprofen, aspirin, naproxen or any human medicine.

Do not give a medication prescribed for a dog, for another cat, or for this cat's previous illness.

Do not decide a cat is just sulking about a change at home. Stress genuinely does put cats off food, and a stressed cat that does not eat is at exactly the same liver risk as a sick one.

Do not wait for a temperature you cannot measure.

Do not assume a cat straining in the litter tray is constipated.

Do not leave a flat cat overnight to see how it is in the morning. Cats that look mildly unwell in the evening are frequently much worse by dawn, because by the time they show anything at all they have usually been ill for a while.

When to get help

Go to a veterinary clinic immediately, out of hours if necessary, for a male cat straining without producing urine, a cat that cannot be roused, open-mouthed or laboured breathing at rest, yellow or brown or white gums, collapse, a flat cold kitten, or any suspicion that a human painkiller has been swallowed.

Book a same-day appointment for a cat that has not eaten in around 24 hours, has hidden itself away and will not come out for food, is sitting hunched and not grooming, or has become flat within days of a fight.

Book an appointment for reduced appetite lasting more than a day, unexplained weight loss, or a senior cat that has quietly become less active and less interested in food.

Recovery is measured in appetite and grooming returning, not just in the cat looking a bit brighter. Keep the food record going until both are back to baseline.

Take the food record, the weights and the gum photograph with you. Cats compensate well and often look better in a consulting room than they did at home an hour earlier, and a written record is frequently what persuades everyone to keep looking.

Clear eyes and a coat that lies flat and glossy mean the cat has been grooming. A dull, spiky, greasy coat means it stopped, and that usually happened before you noticed anything else.