We know chocolate is toxic to dogs. But is one kind worse than the other? Is there any kind of chocolate that is not poisonous? Yes and yes! Basically, which chocolate is most likely to kill a dog that eats it?
The worst chocolate a dog can eat is dark chocolate. It contains the most of a chemical class called methylxanthine. This is the toxin that causes major liver damage, and makes chocolate fatal in dogs. So the less dark the chocolate, the less methylxanthines, and the less toxic. Dark chocolate bars or baking chocolate are the worst offenders. A dog of any size eating dark chocolate warrants a phone call to your vet or local emergency clinic.
Milk chocolate contains methylxanthines, but it has much less, meaning a dog has to eat more of it to get the same toxic amount as if they ate a small amount of dark chocolate. And yes, size of the dog is a huge issue. A 10 lb dog doesn’t have to eat more than a bite of dark chocolate to have problems, while the 100 lb dog needs to eat more chocolate to get the high levels of methylxanthine per pound of dog. Problem is, the 100 lb dogs usually DO eat more! And milk chocolate is highly variable. Save the wrapper (what’s left of it) and if you have a small dog, or a lot was eaten, worth a phone call to the vet.
White chocolate actually has no methylxanthines, so it technically is not toxic – at all! Would I recommend feeding it to your dog? Not really. It is very rich and can upset the tummy. Even if it is not toxic, and your dog’s liver is fine, the rest of the dog’s digestive tract might not be!
What about baked good? Those vary, obviously. Chocolate cake generally is not a concern unless a tiny dogs eats a LOT, and then the concern is more the gastro-intestinal upset that follows, not necessarily the chocolate toxicity. But is there a dark chocolate ganache on that cake? That increases the amount of methylxanthines, and increases the chances of liver toxicity. Chocolate ice cream? Very little methylxanthines, so you’re fine there, but you might get some gas that makes you wish both of you were dead.
Oreos? Not really chocolate. True story – my husband was eating Oreos and dropped one. Our dog snatched it up like a Venus fly trap. My husband panicked – “He ate chocolate! What do I do?!?!” I came into the room and asked what he ate. Realized it was an Oreo and was not worried. After I told my husband those really are not toxic, he then thought Oreos made a great dog treat – also not recommended! Yes, our dogs LOVED them and were not overtly sick, but we had some gas later that no one would admit to.
Bottom line – most 60 lb dogs can grab a snickers mini (or 3) off the table and no panic is needed. If your dog ate chocolate, when do you worry? Here’s a simple calculator (there are many online ones out there) where you plug in the type, amount, and weight of dog, and it tells you how serious this is.
Rule of the thumb: the smaller the dog, or the darker the chocolate, the scarier it is.