Can Small Pets Eat Onion?

Zero tolerance applies here. Onion is firmly on the toxic list for small pets and requires immediate veterinary attention if ingested. Veterinary sources confirm that onion contains substances that can trigger serious reactions. Effects are cumulative — small amounts over time are as dangerous as one large dose. The severity depends on the amount consumed relative to your small pet's size, but there is no established safe dose. Time is critical — call your vet right away if your small pet consumes any part of onion.