A guide to chocolate poisoning in dogs - are you ready for Easter?

A guide to chocolate poisoning in dogs - are you ready for Easter?

Posted 25th March 2019

Easter is just around the corner and as many owners are already aware, chocolate is toxic to dogs. While rarely fatal, chocolate ingestion can result in significant illness. Chocolate is toxic because it contains a chemical called theobromine, as well as caffeine. Both chemicals are used medicinally in humans as a diuretic, heart stimulant, blood vessel dilator and a muscle relaxant. Dogs cannot metabolize theobromine and caffeine as well as people can. This makes them more sensitive to the chemicals’ effects.

The amount of toxic theobromine varies with the type of chocolate. The darker and more bitter the chocolate, the more dangerous it is to dogs. Baking chocolate and gourmet dark chocolate are highly concentrated and contain 130-450 mg of theobromine per ounce, while common milk chocolate only contains about 44-58 mg/ounce. White chocolate barely poses any threat of chocolate poisoning with only 0.25 mg of theobromine per ounce of chocolate (that said, dogs can still get sick from all that fat and sugar, which can cause pancreatitis). To put this in perspective, a medium-sized dog weighing 25 kilograms would only need to eat 1 ounce of baker's chocolate, or 9 ounces of milk chocolate, to potentially show signs of poisoning.

Clinical signs depend on the amount and type of chocolate ingested. For many dogs, the most common clinical signs are vomiting and diarrhoea, increased thirst, panting or restlessness, excessive urination, and a racing heart rate. In severe cases, muscle tremors, seizures, and heart failure can be seen. In older pets that eat a large amount of high quality dark or baking chocolate, sudden death from cardiac arrest may occur, especially in dogs with pre-existing heart disease. Complications (such as developing aspiration pneumonia from vomiting) can make the prognosis for chocolate poisoning worse.

When in doubt, contact your veterinarian or Pet Poison Helpline to see if a poisonous amount of chocolate was ingested. If a toxic amount is ingested, you should have your dog examined by a veterinarian immediately. The sooner the theobromine is removed from the body or the dog is stabilized, the better your dog's prognosis.

Treatment depends on the amount and type of chocolate eaten. If treated early, removal of the chocolate from the stomach by administering medications to induce vomiting and administration of activated charcoal to block absorption of theobromine into the body may be all that is necessary. Activated charcoal may be administered every four to six hours for the first twenty-four hours to reduce the continued resorption and recirculation of theobromine.

It is very common to provide supportive treatments such as intravenous fluid therapy to help stabilize your dog and promote theobromine excretion. All dogs ingesting chocolate should be closely monitored for any signs of agitation, vomiting, diarrhoea, nervousness, irregular heart rhythm, and high blood pressure.

Enjoy your Easter holidays, but always make sure that your pets have no access to your stash of chocolate eggs!