Don’t forget how chocolate, even in tiny amount, will kill a dog. My mother told this to my kids, and they were all confused because our dog ate a bunch of chocolate easter candy and she was fine.
Dogs, and cats although they’re unlikely to actually eat it, cannot eat artificial sweetener as their livers cannot break it down and it becomes toxic to them in moderate quantities. It is often used in a lot of cheaper chocolate, particularly American chocolate. Sugar’s fine though, other than the obvious issues with it.
Somehow dogs cannot eat large amounts of artificial sweetener, got changed into dogs cannot eat small amounts of sugar.
I thought the problem with chocolate is theobromine, same effect as you describe, but bitter and comes from cocoa, so less sweet / more expensive chocolate with higher amount of cocoa is actually more dangerous.
But still, as with any poison, the dose is important, this veterinary page says “One ounce of milk chocolate per pound of body weight is a potentially lethal dose in dogs”, so a dog would need to eat 1/16th of its own weight for it to be deadly, even for small dogs that’s more than a whole bar.
