- Other everyday items to keep from your dog include grapes or raisins
- When people take vitamin D, an overdose in dogs can cause intestinal irritation
Buying it in the supermarket will cost you less than 15p – but onions can set dog owners back hundreds of pounds if your pet has them.
Onions are harmful to dogs and can result in an average pet bill of £339, according to data from pet insurance claims.
Other everyday items to look out for include wine or raisins, which cost owners – or insurers – an average of £503 to treat.
Too many vitamin D tablets will set owners back £640, say a washing powder tablet £554 and accidentally swallowed ibuprofen £640.
The data was compiled by insurance company ManyPets using claims reports from the past 12 months.
According to MayPets veterinarian Dr. Kirsten Ronngren, onions contain disulfides that can destroy a dog’s red blood cells, leading to a condition called hemolytic anemia.
‘Treatment for onion poisoning depends on the size of the pet and how much they have eaten,’ she said.
Vomiting can be as simple as regurgitation, and some pets may do well after treatment, requiring only digestive support and hydration.
However, in more severe cases, a pet may have reached a level of toxicity that requires treatment for anemia.
While humans take vitamin D as a supplement, too much in dogs can cause intestinal upset, increased thirst, and kidney failure. Like ibuprofen, it can be toxic to dogs at lower doses than humans and can cause stomach ulcers and kidney failure.
Dr Ronngren said: ‘That’s why we encourage owners to visit a vet rather than home remedies to find a pet-safe alternative to treating pain.’