Fact or Myth: Chocolate is Toxic for Dogs - McCann Professional Dog Trainers

Fact or Myth: Chocolate is Toxic for Dogs

Easter weekend means fun egg hunts and chocolate abounds. Which may present a lethal danger for your dog.

It's often presented as a myth: Is chocolate really toxic for dogs? We all know a dog who eats chocolate and is just fine, so sometimes people don't believe the facts - chocolate is toxic, but there are variables. 

Toxic Ingredients

The ingredients in chocolate that cause the issue are caffeine and theobromine, methylxanthines that are toxic when ingested in large quantities. These ingredients stimulate the nervous system, change heart rate, increase urine output and can cause a number of other symptoms. The higher the dose, the more dangerous the symptoms. By this, it seems very clear that chocolate is dangerous for dogs. So, why is it that we all know a dog who ate a pile of chocolate and had no real problems. Where the water gets muddied and causes confusion is in the other variables, which include the type of chocolate and the dog's weight.

The Kind of Chocolate

Milk chocolate contains very little of the toxic ingredients, whereas dark chocolate contains much more. Baker's chocolate and pure cocoa powder boast the highest amounts of caffeine and theobromine and can be fatal in very small amounts. This means that a medium sized dog could eat a milk chocolate bar with no ill effects, while the same sized dog ingesting a small square of Baker's chocolate could  suffer some serious toxicity.

The Size of the Dog

The size of the dog is a big contributing factor. For example, a 40 pound dog eating 2 oz of Baker's Chocolate may have a mild toxic reaction including vomiting, diarrhea, trembling, elevated heart rate and increased urination.  The same amount of Baker's Chocolate consumed by a 20 pound dog could be dangerous or even lethal. Look for signs of tremors, seizures, irregular or rapid heartbeat and potential collapse. Finally, a 10 pound dog consuming just 2 oz of Baker's Chocolate is at risk of sudden death. 

When talking about Milk Chocolate, a 40 pound dog can eat 5 oz before they might experience a mild reaction, while a 10 pound dog may have a mild reaction after eating only 2 oz. 

I found this very handy Chocolate Toxicity Calculator to help work through some of the variables. A good rule of thumb would be no chocolate ever, but this may help you understand why Chocolate Toxicity is often rumoured as a myth.

What Should You Do If....?

If your dog gets into chocolate, you should take immediate action and contact your vet. The most important thing is not to delay. Most emergency clinics will have quick access to calculations that will let you know if your dog is in danger. If the amount or type of chocolate is toxic or poses a risk to your dog, the vet can induce vomiting, but it needs to be done quickly to avoid the toxic ingredients moving into the dog's system.

Be safe everyone and as always, Happy Training!



Hi! I'm Shannon and I joined the McCann team in 1999 while training Quincey, my wonderful and spirited Rottweiler, to have good listening skills. I'm the Director of Online Training and Content for McCann Professional Dog Trainers and I enjoy writing about dogs and dog training for the McCann blog. I currently share my life with 2 Tollers (Reggie & Ned) and I love helping people develop the best possible relationship with their 4-legged family members. 

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