Why is my cat vomiting? Causes and when to see a vet
Cats vomit more readily than dogs, and an occasional hairball or a single sick-up in a bright cat is common. But the old idea that regular vomiting is just "a cat thing" is wrong — frequent or repeated vomiting is a sign worth investigating. Two feline emergencies also start with vomiting: eating part of a lily, and swallowing string. Knowing those changes how you respond.
The likely causes
An occasional hairball, brought up as a tube of matted fur, is common in cats that groom a lot, and eating too fast can make a cat bring a meal straight back. A sudden change of diet or a food that does not suit can loosen the stomach. Beyond these, repeated or frequent vomiting points to something more: intestinal parasites, inflammatory bowel disease, an overactive thyroid, kidney disease, pancreatitis, a swallowed object, or a poison. Two are especially dangerous in cats — lily poisoning, where even a nibble of leaf or a lick of pollen can cause fatal kidney failure, and a swallowed string or thread, which can saw through the gut. Our list of foods and plants toxic to cats covers the common household hazards.
What you can safely do at home
This applies only to a single vomit in a cat that is otherwise bright, eating and behaving normally. Take food away for a few hours, leaving water down, then offer a small, plain, easily digested meal and build back to normal. For a cat that gulps its food, a slow feeder or smaller, more frequent meals helps. Regular gentle grooming reduces hairballs. Keep lilies and other toxic plants out of the house entirely, and keep string, thread, tinsel and hair ties well out of reach. Do not give human anti-sickness medicines. If the vomiting repeats, or your cat is off its food, stop home care and call the vet.
See a vet now if you notice any of these
Contact a vet, urgently, if your cat: is vomiting repeatedly, or cannot keep water down; has blood in the vomit; is also flat, hiding, or has stopped eating (with the fatty-liver risk that carries); may have chewed a lily or another toxic plant, which is a same-hour emergency; has string or thread hanging from its mouth or bottom — do not pull it, as that can injure the gut, get to a vet; has a painful or bloated belly; or is losing weight with ongoing vomiting. A cat that keeps vomiting more than about once a week, even between good spells, should be checked — that is not normal.
Common questions
Is it normal for cats to vomit regularly?
No — that's a common myth. An occasional hairball or a rare sick-up in a bright cat is normal, but frequent or repeated vomiting, even if the cat seems otherwise well, is a sign worth investigating. Causes range from diet and parasites to inflammatory bowel disease, thyroid or kidney problems, so a cat vomiting more than about once a week deserves a vet check.
My cat vomited once but seems fine — what should I do?
For a single vomit in a bright, eating cat, rest the stomach for a few hours with water available, then offer a small plain meal and build back to normal. Slow down a gulper's eating and groom regularly if hairballs are the cause. Call the vet if the vomiting repeats, the cat goes off its food, or any other sign appears.
Can vomiting in cats be an emergency?
Yes. Treat it as an emergency if your cat may have eaten any part of a lily (even pollen can cause fatal kidney failure), if there's string or thread hanging from its mouth or bottom (never pull it), if it's vomiting repeatedly, can't keep water down, has blood in the vomit, or is flat, hiding or has a painful belly. Get to a vet straight away in those cases.
Why does my cat keep being sick after eating?
Bringing a meal straight back can be from eating too fast, a food that doesn't suit, or a recent diet change — a slow feeder and smaller, more frequent meals can help a gulper. But repeated vomiting after eating can also signal food intolerance, inflammatory bowel disease or other illness, so if it keeps happening or your cat loses weight, have your vet look into it.
Are hairballs in cats something to worry about?
The odd hairball is normal in cats that groom a lot, and regular brushing reduces them. Worry if your cat retches repeatedly and unproductively, brings up frequent hairballs, or is also off its food, losing weight or constipated — excessive grooming or trouble passing hair can point to skin, gut or other problems that a vet should assess.
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