Foods that are toxic for your cat

Did you know that some foods we eat can be downright deadly for your cat? Scarily, it's also likely that the symptoms don't show on the outside, so it's very important that you as a cat owner know what your cat can and can't eat from our human food. The result can otherwise be severe kidney and liver failure, heart failure and in the worst cases, death.


Chocolate and cocoa are toxic to cats as they contain the substance theobromine. Theobromine has a stimulating effect on the nervous system and cats break down theobromine much more slowly than humans do, which means that if they ingest a certain amount, it can lead to serious poisoning. 

In the case of theobromine, the cat's metabolism is considerably slower than that of humans, which means that if the cat ingests chocolate, it has a much harder time getting rid of theobromine and the substance stays in the body for a longer period of time. When theobromine accumulates in the cat's body, it can affect various organ systems.

It can be difficult to determine the severity of a cat's ingestion of chocolate, but as a general rule it depends on the amount of intake. A lethal dose for a cat is about 80-200 mg/body weight, but poisoning occurs at much lower doses than this. The severity of the poisoning also depends on the cocoa content, how much the cat ingests and how much it weighs, but since cats should not eat chocolate at all, a small amount of chocolate can be extremely harmful to a cat. A guideline is that the darker the chocolate, the more theobromine it contains.

If your cat does ingest chocolate, you should always call your vet immediately for advice, even if your cat seems alert. Should the cat develop symptoms, they are usually noticed within 2-6 hours, but anything from 1 hour to 24 hours is possible. Examples of symptoms may include nausea, increased thirst, vomiting, diarrhoea, palpitations, irregular breathing, restlessness and convulsions. 

You should never try to induce vomiting in your cat by using salt, as this can lead to salt poisoning. If you are concerned that your cat has ingested chocolate, it is always best to call a vet.


All types of onions contain a substance called allicin. This substance is found in both raw and cooked onions and can cause symptoms of poisoning in cats. The onion causes severe anemia in cats and can also damage the liver and other organs. Therefore, never give your cat leftovers that contain onion as an ingredient. Watch for loss of appetite, diarrhoea, vomiting, rapid breathing, heart palpitations, pale mucous membranes, red-coloured urine or abdominal pain in your cat. It is always a good idea to take your cat to the vet if these symptoms can be linked to your cat having ingested onions.

Pork and sausages

Although there is not always a danger in giving your cat a small piece of sausage, it is important to remember that sausage is both fatty and salty, which in turn can cause diarrhoea and vomiting and lead to pancreatic problems. Therefore, we recommend not giving your cat even a small taste, as all cats are more or less sensitive.

The meat itself from both pork and sausages is not the big danger here, but it is about the fact that they are usually flavoured with a lot of spices and onions, which in turn can cause severe poisoning in the cat. If you want to give your cat a taste, it is therefore best to give it meat that is not flavoured in any way.

Grapes and raisins

Grapes and raisins are very dangerous for your cat. Your cat may experience serious symptoms such as vomiting, diarrhoea, abdominal pain and lethargy. This can, within 1-3 days, lead to kidney damage which also manifests itself in vomiting, abdominal pain but also poor or no urination. It is therefore important to seek early medical attention if you know that your cat has ingested grapes or raisins. Deaths have been reported with as few as seven grapes. So never keep grapes around unattended.

Dough and alcohol

When dough ferments in the stomach, the cat can get alcohol poisoning, which can cause symptoms such as abdominal pain, bloating, vomiting and wobbliness.


Avocados can damage both the heart and gastrointestinal tract of your cat, but also most other animals. If you have an avocado tree at home, make sure your cat doesn't get to it, as even the leaves contain high levels of the substance that poisons cats.

Bitter almond

The substance cyanide, found in bitter almonds, is lethal to cats and other animals in large quantities. Cyanide blocks the uptake of oxygen by cells and can cause symptoms such as increased breathing rate, difficulty breathing, bright red mucous membranes, weakness, nausea, vomiting and loss of consciousness. Therefore, make sure your cat does not eat bitter almonds or certain biscuits and almond paste that usually contain bitter almonds.

Things to bear in mind

Cats usually eat everywhere in the home, so it's important to keep a close eye on your cat when cooking and eating foods that your cat can't tolerate. Poisoning can happen quickly, and it can be serious, so it's a good idea for your vet to know what your cat has ingested.

See a vet

If your cat shows serious symptoms, it is best to go in as an emergency to stop the poisoning as possible and prevent serious illness. If you are unsure whether your cat has ingested something it cannot tolerate, it may be a good idea to contact a digital vet for advice. As a Lassie insurance customer, you always have unlimited calls to digital vet.

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