Chocolate poisoning – know what to do

1st January 2017


Chocolate contains a stimulant called theobromine that’s poisonous to dogs. The amount of theobromine differs from one chocolate to another. Dark chocolate tends to have the highest levels of theobromine, however milk and white chocolate can have theobromine added and will therefore pose the same level of danger.


What does theobromine do?

Theobromine is a stimulant similar to caffeine. It mainly affects the heart, central nervous system and kidneys. The symptoms occur between 4 and 24 hours after chocolate has been eaten.


Signs of chocolate poisoning include;

  • Vomiting
  • Diarrhoea
  • Restlessness
  • Hyperactivity
  • Rapid breathing
  • Incoordination
  • Very fast heart rate
  • Seizures


How much chocolate is too much for my dog?

At Bollington Veterinary Centre we recommend a ‘no chocolate’ policy for dogs. However, dogs don’t necessarily listen to what we have to say, and it’s common for us to see animals that have stolen some chocolates off the table.


Don’t hesitate – call us immediately if you dog has eaten chocolate


We are very experienced when it comes to dealing with dogs who have eaten chocolate. Make sure you know which type of chocolate has been eaten, and if possible bring the wrapping paper with the list of ingredients. We can then calculate how much theobromine has been eaten, and determine what treatment needs to be given to avoid a problem.


Signs of poisoning will be seen even at low levels of ingestion. For example, a 30kg dog that has eaten 200g milk chocolate is likely to have a mild tummy upset with some vomiting and diarrhoea. However if they have eaten 500g of milk chocolate, it is likely that heart problems will be seen.


What should you do if your dog has eaten chocolate?

If you think your dog has eaten chocolate please contact us at Bollington Veterinary Centre on 01625 573375 immediately.



There is no antidote to theobromine. Our vets will usually give an injection to make your dog vomit to try to remove as much chocolate out of the system as possible. Activated charcoal may also be offered to help reduce absorption. Other treatments will depend on the signs your dog is showing. For example, they may need intravenous fluids (a drip), drugs to reduce and stabilise the heart rate, blood pressure and potential seizure activity.


Good prognosis

The good news is that with early action and treatment, even in dogs that have eaten large amounts of chocolate, the prognosis for a poisoned dog is usually good.