Chocolate is poisonous for pets – fact or fiction?

You've read the warnings about feeding chocolate to pets – especially dogs. But are they true?

There are lots of types of chocolate (blocks, powder, ice cream, cakes, biscuits... the list goes on). Are they all bad? If your dog sneaks a lick of chocolate ice cream, is this dangerous?

Let's look at the facts about chocolate, dogs (and cats!).

What’s in chocolate?

Chocolate is made from the fruit (pods) of the cacao tree. Cacao farmers harvest the pods, split them open and scoop out the bitter seeds. These seeds contain theobromine, caffeine and fat (cocoa butter) – remember these. The farmers leave the seeds under banana leaves for about a week where they ferment. This creates the chocolate flavour.

The fermented seeds are processed to create:

  • chocolate liquor – the liquid that results from grinding the seeds
  • cocoa butter – the fat removed from the chocolate liquor
  • cocoa powder – the solid left after cocoa butter is removed from the chocolate liquor.

These contain different amounts of theobromine, caffeine and fat. For example, cocoa butter has no theobromine or caffeine (it's all fat). Cocoa powder has no fat, but lots of theobromine and some caffeine. The liquor contains everything.

The liquor, butter and powder are used to make the chocolate products we find in the shops. Labels on these products usually say things like:

  • unsweetened (baking) chocolate or coca – this is almost straight chocolate liquor
  • dark chocolate – this contains 35–85% chocolate liquor
  • milk chocolate – this contains at least 10% chocolate liquor.

Now, let's look at how chocolate affects dogs.

What happens if a dog eats chocolate?

It depends on how much theobromine, caffeine and fat the chocolate contains and how much the dog eats.


Theobromine is toxic to dogs. This is because they can't metabolise well (unlike us). After eating it, blood levels build up over 6 to 12 hours and cause signs of toxicity.

Theobromine is in the same family of chemicals as caffeine. This helps us understand its effects. A dog eating theobromine is a bit like a person drinking far too many cups of coffee. Theobromine causes:

  • nausea, vomiting and diarrhoea
  • hyperactivity (restlessness, anxiety)
  • increased production of urine (leading to drinking more and dehydration)
  • racing heart rate (sometimes changes the rhythm too)
  • tremors
  • seizures
  • coma and death.

The severity of signs depends on how much theobromine is eaten. Now remember, different chocolate products contain different amounts of theobromine. White chocolate has none (it only has cocoa butter in it). Milk chocolate has some and dark chocolate/baker's chocolate can have a lot.


Caffeine has the same effects as theobromine.


The fat (and sugar) in chocolate can cause a temporary upset tummy. In most cases of dogs eating chocolate, there’ll be some diarrhoea.

The bigger issue comes from what the chocolate is mixed with. For example, the dog who swipes a chocolate cheesecake off the table will eat a lot of fat (even if not much chocolate). This can trigger a very serious condition called pancreatitis.

Signs of pancreatitis include nausea, vomiting and tummy pain. These can occur 24–72 hours after a fatty meal.

Can cats eat chocolate?

Cats have the same problems with theobromine as dogs. Fortunately, cats don’t usually go for sweet foods, so they tend not to eat chocolate.

What should I do if my dog has eaten chocolate?

You can use a chocolate calculator or call your vet to see if the amount of chocolate is enough to cause problems. You'll need to tell the vet your pet's weight, the type of chocolate and the amount eaten.

Most ingestions only cause an upset tummy that resolves in 24 hours. But around Easter and Chris