Why does my cat keep being sick? Causes & treatment

If your cat has been sick but is otherwise acting normal, it’s likely a one-off. Keep an eye on whether they’re off their food, newly lethargic or sick any other times.

If your cat has been sick once or twice but otherwise appears fine:

• Try offering smaller and more frequent meals, rather than their usual portions.

• Try offering plain cooked food like boneless and skinless chicken or white fish.

• If they keep their down, continue to offer them small amounts every few hours for the next 24 hours.

• If there’s no further vomiting, then you can go back to their usual routine.

Repeated vomiting in a short period of time, or over more than 24 hours needs to be taken seriously. 

Just as with humans, vomiting can dehydrate your cat and pose a risk to their health. If you see any of these signs, you should contact your vet as soon as possible:

• Your cat can’t keep water down.

• They have blood in their vomit.

• They have pale or cold gums.

• They’re displaying signs of listlessness, diarrhoea, fever, or another illness.

A common reason cats throw up is hairballs. Hairballs are clumps of hair that collect in your cat’s stomach from grooming. Because they use their tongues to clean, they end up swallowing a lot of dead fur. Usually, this hair passes through their gastrointestinal system, but sometimes the clumps become too big to pass through the stomach and they have to be vomited instead.

If your cat has a big hairball, they may be sick a few times in a row to resolve this completely. Symptoms of hairballs can include lethargy and loss of appetite. (You’d go off your food too if your stomach was full of hair). But once the hairball has passed, they should go back to acting normally.

If your cat has vomited repeatedly, you should take them to the vet. Even if they seem fine. Cats are masters at concealing when they feel unwell. And you don’t know if there is an underlying condition they’re not showing signs of. 

Inspecting your cat’s vomit might be a bit gross. But it can tell you important things about their health.

Hairball vomit will contain lumps of matted hair. Despite being called hairballs, they’re usually more elongated and sausage-shaped, because they form in your cat’s gastrointestinal tract.

Bile is produced in the liver and helps to break down your cat's food. your cat may vomit it up as either a yellow or greenish liquid or foam. This is often brought up if a cat vomits on an empty stomach.

A white, foamy substance means that your cat is being sick on an empty stomach. You might spot grass in there if they’re an outdoor cat. Which means they ate grass because they were feeling sick. And wanted to throw up.

Brown vomit has a couple of potential meanings. If it looks chunky, like their food, it means the food didn’t make it past the stomach.

If the liquid is brown, black, pink or red, this might be due to intestinal bleeding.. if you’re worried at all, take them to the vet.

Blood can be pretty scary to see in your cat’s vomit. It can be caused by an internal injury, irritation, or disease, and could be coming from anywhere along the upper GI tract. If you see blood, it’s time to take them to the vet.

If you see worms in your cat’s vomit, this could signify a significant parasitic burden. Worms are parasites that can take up residence in your cat’s digestion tract. And in large quantities can threaten their health. Take them to a vet if you spot worms in their vomit for treatment. 

if your cat is vomiting frequently in a short period of time, or if they vomit regularly over a longer period of time,  has ingested something toxic, has blood  in their vomit, or also has other symptoms like diarrhoea, take them to the vet. 

If it’s just a one-off vomit, follow the advice above or check in with your vet. But if your cat has an underlying condition, it’s important to treat the problem to help reduce the vomiting. 

Food allergies – a common cause of vomiting in cats – can help to be treated by your vet. Who might recommend a special diet.  

If your cat’s vomiting is severe, your vet might keep them in overnight. To reverse any dehydration with fluids and medication.

While there could be more serious causes of your cat’s vomiting, which should be diagnosed by your vet, we have a few tips for you to try if your cat is healthy and experiences occasional vomiting:

Regular grooming – Keeping your cat well groomed and brushed helps to reduce the number of hairballs they vomit. Giving them a hairball supplement can also help them pass the hair more easily in their poop. Rather than vomiting it back up.

Enrichment food puzzles and toys – If your cat tends to be sick after eating, it could be because they ate too fast. It’s okay – we all get a little too excited over dinner sometime. Feeding them in a slow feeder might be a good way to prevent them from eating too quickly.

Consider switching to a highly-digestible, low residue diet – If your cat has a bit of a sensitive stomach, think about switching them to a more suitable food. (KatKin can be a suitable option for cats with sensitive stomachs.)