Chocolate contains the chemical Theobromine which is toxic to your dogs nervous and cardiovascular systems. Unfortunately it can’t be metabolized fast enough in a dog and can cause toxic levels to form. It’s important to note that senior dogs are much more susceptible to chocolate poisining.
If your dog accidentally eats your chocolate, here is a loose guideline you can follow to judge toxicity:
Semi-sweet chocolate - 1/3 ounce to 1 full ounce per body weight. Example: a 20 pound dog would have to ingest about 6 ounces to show negative reactions to the nervous system.
Bakers chocolate – 0.1 ounce to 0.3 ounces per body weight. Example: a 20 pound dog would have to ingest about 2 ounces to show negative reactions to the nervous system.
Look at it this way, all it takes is just 1 ounce for a 10 pound dog!
Here are some signs of chocolate poisoning to watch out for:
Vomiting, diarrhea and hyperactivity, excessive panting, increased urination, increased thirst and high blood pressure.
If you know for certain that your dog has eaten a large amount of chocolate and hasn’t yet vomited you can try and give him a 50/50 mix of hydrogen peroxide and water to induce vomiting. Once you’ve done this, take your dog into the vet immediately.
Heart arrhythmia are a sign of later symptoms. As the toxins are absorbed, the heart can begin to beat too fast and irregular, causing heart arrhythmia.
Other later symptoms can include seizures and even coma.
As you already know, it’s really important to keep chocolate away from your dog. Dog’s love sweets and don’t have any clue that chocolate isn’t good for them. Also, it's always good to keep 3% hydrogen peroxide on hand. The quicker you act the better the chances of keeping your dog safe, happy and healthy. My vet has told me that if your dog is treated within about 4-5 hours, they have the highest chances of survival if they ingested a toxic amount.