As you may be aware, chocolate contains Theobromine and Caffeine. If you would like to know more about why chocolate is so problematic, you can find that discussion here
These are both vasodilators as well as stimulants. This means that one of the first symptoms that you will see is that your dog all of a sudden has too much energy. He may start pacing around, panting, shaking, and twitching.
From there, your dog may start to exhibit signs of extreme thirst (from needing to urinate more frequently), and even possibly diarrhea.
Then, depending on the severity, your dog may then begin to have seizures, and may even pass out and fall into a coma.
At the most extreme end, your dog’s heart will stop, and she will die.
This is why chocolate poisoning is not a joking matter. It is also why you CANNOT wait until your dog begins to show symptoms of chocolate poisoning.
As soon as you suspect that your dog has eaten chocolate, you need to begin to take actions to try to help. The symptoms of dog eating chocolate are clear warning signs that something is wrong and that you need to take action immediately.
And again, here is the list of symptoms in list form for you: