No, cats can’t eat onions.
Onions cause cats anemia because they contain a substance that destroys feline red blood cells.
Onions can be very dangerous for cats and other members of the onion family including shallots, garlic, leeks, and chives should also be kept away from pets.
This is because these plants contain an ingredient called thiosulphate which can damage red blood cells in both cats and dogs.
It’s not only onions that can harm your cat, but also garlic and leeks.
Cats lack the enzyme that breaks down thiosulphate which means it builds up in their system causing haemolytic anemia.
Can onions kill cats?
Since onions contain a substance that destroys feline red blood cells, it can cause anemia in cats.
Anemia occurs when red blood cells get destroyed faster than they can be replaced and causes your cat not to have enough healthy red blood cells to carry oxygen throughout its body.
Symptoms of anemia include pale gums, increased heart rate, weakness, lethargy, and exercise intolerance.
In severe cases of anemia, a cat can collapse or even die from lack of oxygen if left untreated.
Kittens are particularly susceptible to anemia since they require more nutrition than adults for healthy growth.
This is because kittens need red blood cells to carry oxygen throughout their bodies. If they don’t have enough red blood cells, they can experience a sudden collapse and can even die.
Ensure that you feed your kittens an iron-rich diet.
Can cats eat onions in very small amounts?
Since even just a small amount of onions can cause anemia in cats, it’s best you don’t give your cat any at all.
However, if you have given your cat some onion and they are showing symptoms of anemia, there are treatments available so that you can help them recover.
If it has been less than six hours since it ate the onion, you can induce vomiting to expel the onion from their stomach.
If your cat is showing signs of anemia, you’ll need to seek veterinary attention immediately.
The vet may prescribe some iron supplements for your cat or even a blood transfusion if they are severely anemic.
However, since cats are obligate carnivores, they must get their nutrients from animal products and not plant products like onions.
So it is recommended to feed your cat a diet that is high in protein and fat with no carbohydrates or other vegetable-based food items.
Can cats eat spring onions, instead?
Spring onions or scallions are okay to feed your cat as long as they’re cooked.
Onions and other members of the onion family including shallots, garlic, leeks, and chives should not be fed to pets at all.
These plants contain an ingredient called thiosulphate which can damage red blood cells in both cats and dogs.
What to do if my cat ate an onion?
If you’re worried that your cat has eaten onion or other members of the onion family, you should induce vomiting to expel it from their stomach.
However, since red blood cells are being destroyed in your cat’s body already, symptoms such as pale gums and increased heart rate can be hard to notice.
Since even just a small amount of onions can cause anemia in cats, it’s best to take your cat to the vet immediately.
Your vet will be able to do a blood test and diagnose your cat with anemia caused by eating onion or other members of the onion family.
What should I feed my cat instead of onions?
Cats can’t derive nutrition from plant-based products so they need a diet that is high in protein and fat with no carbohydrates or other vegetable-based food items.
Choose cat food that contains meat as the first ingredient.
You should also avoid feeding your cat table scraps since these are often made from plants including onions, celery, and other members of the onion family.
If you do want to feed your cat some vegetables, be sure to cook them first since raw vegetables are dangerous for animals who cannot digest plant matter properly.
Some safe vegetables to give your cat include cooked carrots, peas, green beans, cucumbers, zucchini, and butternut squash.