What happens if my dog eats a little bit of onion?

Onions contain a toxic principle known as N-propyl disulfide. This compound causes a breakdown of red blood cells, leading to anemia in dogs. The toxin causes oxidative damage to your dog’s red blood cells by attaching to the oxygen molecules in your dog’s red blood cells.

How much onion is toxic to small dogs?

05% of their body weight in onions to be a toxic amount. For a 45 pound dog, that’s one small onion.

How long after eating onion will a dog get sick?

While vomiting and diarrhea may occur within one day, it may take several days to a week after your pet eats onions for symptoms of anemia to appear.