Although chocolate is one of our favourite treats, many people are unaware of the fact that chocolate can be toxic (and sometimes fatal) when shared with our canine friends. Chocolate is poisonous to dogs; however, the hazard of chocolate to your dog depends on the type of chocolate, the amount consumed and your dog’s size. In large enough amounts, chocolate and cocoa products can kill your dog.
Why not chocolate?
The toxic component of chocolate is theobromine, which comes from the beans of the cacao tree. Humans easily metabolize theobromine, but dogs process it much more slowly, allowing it to build up to toxic levels in their system.
A large dog can consume more chocolate than a small dog before suffering ill effects.
A small amount of chocolate will probably only give your dog an upset stomach with vomiting or diarrhea.
With large amounts, theobromine can produce muscle tremors, seizures, an irregular heartbeat, internal bleeding or a heart attack. The onset of theobromine poisoning is usually marked by severe hyperactivity.
The usual treatment for theobromine poisoning is to induce vomiting within two hours of ingestion. If you are worried or suspect that your dog may have eaten a large quantity of chocolate and they are showing any of the signs listed above, call your veterinarian immediately.
A single piece of chocolate should not be a problem. A single piece doesn’t contain a large enough theobromine dosage to harm your dog; however, if you have a small dog that has eaten a box of chocolates, you need to call and go to your veterinarian right away. Do not wait.
Different chocolate types have different theobromine levels. Cocoa, cooking chocolate and dark chocolate contain the highest levels, while milk chocolate and white chocolate have the lowest. If you’re dealing with any quantity of dark or bitter chocolate, err on the side of caution. The high level of theobromine in dark chocolate means it takes only a very small amount to poison a dog.
What are the signs of chocolate toxicity?
Signs most commonly occur within 12 hours of ingesting the chocolate, and include:
vomiting and diarrhoea
trembling and muscle spasms
increased excitement, irritability or nervousness
increased heart rate
excessive thirst and excessive urination (in higher doses)
death (rare – usually due to cardiac disturbances)
What treatment options are available?
As there is no antitoxin available for theobromine, the only treatment available is supportive therapy.
If an animal is presented less than four hours after ingestion, vomiting will be induced. After four hours, activated charcoal is administered, which helps prevent further absorption from the gut.
Intravenous therapy is always indicated to help flush out the toxin from the body faster, and is also essential to prevent and/or treat the severe dehydration that can occur as a consequence of the vomiting, diarrhoea and/or increased urination.
Complications of theobromine toxicity include seizures, muscle tremors and disturbances of heart rhythm. Anticonvulsant and antiarrhythmic dogs may be indicated in these cases.
How much chocolate should I be worried about?
It depends on the type of chocolate and the weight of the dog.
Check out this interactive Chocolate Calculator (just remember to change the measurements to metric kilograms and grams).