My cat is vomiting: what it means and when to worry

Vomiting or regurgitation: how to tell them apart

They are not the same, and it helps the vet to know which one you saw.

Vomiting:

• Beforehand, the cat drools, swallows saliva several times, and retches.
• The belly contracts forcefully.
• They bring up food or fluid from the stomach and the first part of the intestine.

Regurgitation:

• It is passive: it comes up without effort or retching.
• It is usually undigested food.
• Sometimes it has a tube shape, like the esophagus.

Hairballs that cats bring up are also often elongated, like a cigar, because of the tube they pass through.

What it means depending on how the vomit looks

Color or appearance can give clues, but the veterinary sources we consulted do not link each color to a specific cause. What marks urgency is how often they vomit and what other symptoms they have.

My cat vomits hair: is that normal?

Bringing up a hairball now and then is normal: when grooming, the rough tongue makes them swallow loose hair, which is not digested. Almost all of it passes in the feces, but some can stay in the stomach and form a ball.

• Every one or two weeks: no cause for concern.
• Long-haired cats: breeds such as the Persian or Maine Coon are at higher risk.
• During shedding season they appear more often. Kittens and young cats have them less than older cats.
• If they groom too much, they may have a skin problem related to a food allergy.

Rarely, a large hairball blocks the intestine, and without surgery it can be fatal. So take them to the vet without delay if they are lethargic, stop eating for more than a day or two, or have repeated retching or vomiting.

Do not give laxatives or “anti-hairball” diets unless your vet advises it.

My cat vomits and won’t eat

A cat that vomits and also eats less needs to see the vet soon. If they have gone more than a day or two without eating, don’t wait any longer.

Also think about whether they could have eaten something toxic:

• Lilies: any part of the plant, the pollen, or the vase water. Early signs are drooling, vomiting, loss of appetite, and lethargy, between 1 and 6 hours later.
• Paracetamol: even a piece of a tablet can kill a cat. Signs include vomiting, loss of appetite, and brown gums.

In both cases it is an emergency: go to the vet immediately.

Later we will have a guide on My cat won’t eat.

Most common causes

Things they ate:

• Toxic plants or spoiled food.
• Human medicines.
• String, yarn, clips, rubber bands, or other objects.
• Toxic substances such as antifreeze, chocolate, or onion.

Health problems:

• Hairballs and constipation.
• Internal parasites.
• Inflammatory bowel disease, food allergy, or intestinal obstruction.
• Kidney or liver disease, pancreatitis, diabetes, or hyperthyroidism.
• Infections and tumors.

What to do at home (and what not to do)

Yes:

• Watch them: note how many times they vomit, what the vomit looks like, and whether they eat, drink, and stay active. Those details decide whether you need the vet.
• Leave water available at all times. Don’t take it away unless the vet says so: that can worsen dehydration.
• Check whether they had access to plants, medicines, string, or small objects.

No:

• Don’t give human medicines, or any medicine the vet hasn’t prescribed. Paracetamol, for example, is highly toxic to cats.
• Don’t give laxatives or hairball remedies on your own.
• Don’t wait if any of the urgent signs appear.

How to prevent vomiting

• Brush them every day, especially if they are long-haired or shedding.
• Don’t keep lilies in the house or garden.
• Store medicines out of reach, ideally in a cupboard.
• Put away string, yarn, clips, and rubber bands.
• Don’t give chocolate or onion.
• Control parasites: internal parasites can cause vomiting. Ask your vet how to deworm them; we explain it in Deworming your cat.
• Control fleas: by swallowing an infected flea, the cat can get a tapeworm. See our guide on fleas in cats.