My cat is vomiting: when it’s normal and when it’s an emergency

Many people think it's “normal” for cats to vomit often. The occasional hairball, yes. But frequent vomiting isn't normal and is worth checking.

Common harmless causes

• Hairballs, especially in long-haired cats and during shedding season. Regular brushing helps.
• Eating too fast and bringing food back up, almost undigested, shortly after. Try smaller portions or a slow-feeder bowl.
• A sudden change of food. Change food gradually, over 7–10 days.

See a vet immediately if

• your cat vomits again and again within a few hours, or can't keep even water down
• there's blood in the vomit, or it looks like coffee grounds
• it is weak, hiding, or its belly is painful
• a male cat keeps going to the litter box but passes no urine: a possible blockage, and an emergency
• it may have eaten string, a hair tie, a lily, medicine or something toxic
• it's a kitten or an elderly cat

If you see string coming out of the mouth or bottom, don't pull it. It can injure the gut. Go to the vet straight away.

Book an appointment in the next few days if

• it vomits more than once a week, even if otherwise well
• it's losing weight or drinking and urinating more than before
• vomiting comes with diarrhoea

Chronic vomiting can be caused by food intolerance, gut inflammation, kidney or thyroid problems, all of which are easier to manage when found early.

Be careful with fasting

A cat that doesn't eat for more than 24 hours is at risk of hepatic lipidosis, a serious liver condition. Don't withhold food for long “to rest the stomach” on your own. Ask your vet first.

See also what to do when your cat won't eat and urinary problems. For an emergency, find an open vet now. Otherwise, book an appointment or ask a vet.

Frequently asked questions

How much vomiting is “normal” for a cat?

The occasional hairball. If your cat vomits more than once a week, it’s worth a check-up.

My cat is vomiting foam. What does it mean?

It can come from an empty stomach or irritation, but also from more serious problems. If it keeps happening or your cat seems unwell, see a vet.

Does cat grass help?

Some cats eat it and bring up hair. It doesn’t replace brushing, or a check-up if vomiting is frequent.