Cacao and chocolate contain a group of substances called metyllxanthinalkaloids which are potentially life threatening for dogs. Teobromine and caffeine, and teophyllin are among these substances. Teobromine stimulates the central nervous system by releasing ephedrine. Teobromine can be found in coffee, cola, chocolate, cacao, tea and chocolate cake. A plate of dark chocolate can be deadly to a dog weighing 22 kilos.

After the cacao or chocolate has been digested, the teobromine is absorbed by the liver, transported through the gall bladder back to the intestines and starts the same round once more. This means that the dog is not able to rid itself of these substances, but keeps being poisoned again and again. Humans are able to rid themselves of the substances within 3 hours, but they can stay inside the dog for as much as 20 hours. Even if a small amount wouldn’t cause poisoning, it could lead to irregular pulse and breathing.

There need not be a big bite of chocolate for your dog to be unfortunate. Roughly 30 grams (2 g cacao pr kilo body weight) of dark chocolate pr kilo body weight is enough to cause serious poisoning. The ephedrine can cause increased heart activity, hallucinations, serious diarrhoea, epileptic seizures, heart attacks and internal bleeding.

During WW2 by-products from the cacao industry was being tested as a supplement to household animals. The test showed that even 2 grams per kilo body weight per day could be lethal to the dog over time.

Teobromine can also provoke epileptic seizures in dogs having been diagnosed with epilepsy or in dogs that have not been diagnosed yet but have it as a latent bug.

How toxic chocolate is to dogs will vary from dog to dog, but is to a great extent reliable on the dog’s weight. A big dog like the mastiff will probably not be poisoned by a small piece of chocolate. A simple reminder is to not teach our dog to like chocolate in the first place. A dog’s tolerance to teobromine varies, but have the scientists puzzled as to why these variations occur.

Type of chocolate and its teobromine content per 10 grams of chocolate. Deadly dose pr 10kg body weight. Ref. Canine Medical Information
Milk chocolate has 44-66 mg/oz,
Dark chocolate 450 mg/oz
Baking/bitter chocolate or cocoa powder varies between150-600 mg/oz.

The symptoms of chocolate food poisoning is vomiting, hyper activity, restlessness, hyper sensitive to touch, quickened heart beat and breathing, lacking control in his muscles, muscular contractions and lacking control over toilet habits. The symptoms are bound to repeat themselves in intervals. After a while the dog will become weaker and go into a coma, and will die due to heart failure and / or internal bleeding. The vet will have an antidote so that the only solution is to bring the dog as quickly as possible to the nearest vet’s office.