Dogs and Chocolate
We've all heard it: "dogs are allergic to chocolate." Actually, that's not such a bad way to think of it, and keeping your dog away from any and all chocolate is a must. But it is a good idea to understand the problem dogs have with chocolate, so you can be prepared in case there is a problem.
It's actually not an "allergy." As you know, chocolate contains caffeine. But it also contains a related compound called theobromine, and this is what dogs are very sensitive to. Symptoms of theobromine poisoning include obvious stomach pain, restlessness, drooling, and vomiting... and the vomit may in fact smell like chocolate, which is a definite giveaway. If enough theobromine has been consumed, then more severe symptoms will follow, such as rapid breathing, increased heart rate, trembling, and cyanotic (bluish) gums. Convulsions and death may follow. It's serious, and if your dog manages to get his paws on some chocolate, get on the phone with the vet or poison control center immediately.
-Read the whole article