Last Updated: 07/05/2025
Wanting to know more about chocolate toxicity? Find out why chocolate is toxic symptoms of toxicity and a chocolate toxicity calculator from our vet team.
Author: Dr Carla Paszkowski BVSc (Hons)
Reading Time: 14 minutes - short read
Ahh, chocolate. Ever since its invention in 450BC, humans have adored chocolate in every form. From hot chocolate to cakes to Easter eggs, chocolate has permeated throughout almost every culinary culture on the planet.
But as harmless as chocolate may be for us, the same can't be said for our furry friends.
Chocolate is poisonous to dogs and cats because it contains chemicals known as methylxanthines. In particular, the methylxanthines chocolate contains are theobromine and caffeine. Both of these are toxic to cats and dogs because they can't metabolise these compounds as well as humans can.
Both caffeine and theobromine produce similar effects, with the theobromine effects lasting much longer than those of caffeine. Symptoms may include:
Vomiting
Diarrhoea
Hyperactivity
Tremors
Seizures
Bradycardia (speeding heart rhythm progressing to an abnormal beat)
Death in severe cases
There are many levels of chocolate dilution: white, milk, dark milk, dark, bitter black, etc. Generally, the darker the chocolate, the higher the cocoa content, which means the more theobromine and caffeine there is. So the darker the chocolate, the higher the toxicity.
White chocolate contains virtually zero theobromine. However it does pose a risk of pancreatitis due to its high fat content so dogs should not eat white chocolate either. Milk chocolate contains 44 mg per ounce of theobromine, and dark chocolate contains around 390 mg per ounce.
In order to calculate whether your dog has ingested a toxic level of theobromine, you will need to know your dog's weight, the darkness of the chocolate, and how many grams were likely consumed. If it is not clear how much chocolate was actually consumed, the largest possible amount should be determined based on how much chocolate is missing.
1. Do a quick calculation with a chocolate toxicity calculator. This will help you determine the level of risk and therefore urgency. Please note that if your dog is showing symptoms, the first step should be to get your dog to a vet right away.
2. If your dog has only just eaten the chocolate within 10 minutes, it may be possible to induce vomiting. We suggest phoning your vet for advice on how to safely make your dog vomit.
3. If your dog ingested the chocolate more than 10 minutes prior, AND it is a toxic dose, hospitalization and support are needed.
It can take four days for the theobromine to work its way out of your dogâs system. This means that your dog may exhibit signs for a few days after ingestion, and ongoing hospitalisation may be required.
Aside from theobromine and caffeine toxicity, chocolate poses another significant risk to pets due to its high fat content. A sudden high fat meal (such as demolishing a block of chocolate) can create a deadly disease called pancreatitis.
The high level of fat stimulates the pancreas to work overtime as it attempts to secrete enough digestive enzymes to metabolise it. This leads to an inflamed and extremely painful pancreas. Vomiting, diarrhea, and abdominal pain are just the beginning of this illness - it may soon progress to infection, fever, and irreversible organ damage. Dogs who suffer from pancreatitis may never be able to eat fatty treats again without a flare up.
Read more about pancreatitis in dogs
With all this in mind, this doesn't mean that your dog has to miss out on a treat of their own! Check out our vet tips on the best dog treats, and our recommendations below for something a little extra special for your fur baby!
Want to know more? Check out our Discover Page for more tips from our expert vets on keeping your pets happy and healthy.
