Garlic and other allium vegetables are harmful to cats, and may eventually lead to anemia. While it seems odd that a vegetable would be toxic to them.
The reason that allium vegetables are toxic to cats is because of a toxin called thiosulphate which they have a hard time digesting.
Their sensitivity to garlic, or how severe it will affect them, depends on the cat’s size and their innate sensitivity towards allium vegetables. So it is considered to be a rule of thumb that even one bite may be poisonous, so avoid feeding them foods containing allium vegetables at all.
When a cat is suspected to have eaten garlic, the best course of action for a nearby human is to either go to the nearest vet or contact the local poison control. When at the vet, the cat will most likely receive a potassium infusion that will help restore proper pH levels and even result in better kidney function.
References:
Eppler, J. (2021, September 23). Can Cats Eat Garlic Bread? (The Risks!). Pet Food Fuss. https://petfoodfuss.com/cats/can-cats-eat-garlic-bread/
UntamedCatFood. (n.d.). Can cats eat garlic? Get the answer NOW! Untamed. https://www.untamedcatfood.com/blogs/nutrition/can-cats-eat-garlic#:%7E:text=Garlic%20bread%20is%20downright%20toxic,and%20how%20susceptible%20they%20are.
