[Pebbles82]

I think it's well accepted that chocolate is toxic to most pets. It's more about the dosage. It contains theobromine which would also poison humans if we ate enough of it but it would be a vast amount to eat in one go for a human (eg a truckload) to be toxic. Whereas for pets a much smaller amount can be toxic. It's particularly well known to be toxic for dogs but the same goes for all small pets really.

The thing is a dog is much more likely to eat all of a large bar of chocolate. Hamsters tend to eat tiny amounts. Even a tiny amount could still be toxic to a hamster (dark chocolate more so than milk as has more theobromine) but a very tiny amount probably wouldn't poison a hamster as it's the dose that causes the toxicity.

Even so they need to avoid eating chocolate! I think the amount in nutella and the amount your hamster had is probably fine. Signs would be stomach upset or diarrhoea initially probably. Or general illness as well of course.

The theobromine is a bit like caffeine so any effects would probably be hyperactivity and happen quite quickly so if the hamster is fine for 24 hours it's probably ok. I suspect it will be fake milk chocolate in Nutella! Or some chocolate flavoured type thing - not sure.