Why is Chocolate Poisonous to Dogs?

- Written by Bhagyashree Rambabu

Why can’t dogs eat the delicious goodness, that we all love and know, as chocolate?

Chocolate is primarily made of cocoa that is derived from the roasted seeds of Theobroma cacao. The toxic components in this substance are theobromine and caffeine. The concentration of caffeine in chocolate is significantly less than the concentration of theobromine, however both substances contribute to the clinical syndrome seen in chocolate toxicosis.

How much chocolate is toxic to dogs?

A larger dog can consume more chocolate, without being affected, than a smaller dog. Dark chocolate is more dangerous to dogs than milk chocolate. A very small amount of chocolate may not have any effect on the dog. Therefore, the toxicity of chocolate is dose-related, so the overall effect depends on factors such as the size of the dog, the type of chocolate and the amount consumed. The initial symptoms include hyperactivity, vomiting and diarrhea. Larger amounts of theobromine can cause muscle tremors, seizures, and even result in death.

What happens, on a cellular level, if a dog consumed chocolate?

Both, theobromine and caffeine, competitively inhibit adenosine receptors that consequently increases neural activity and stimulates the central nervous system. The substances also cause increased levels of epinephrine and norepinephrine in the blood, resulting in elevated heart rate and blood pressure, and abnormal heart rhythms. Moreover, they also increase intracellular calcium levels by increasing cellular calcium entry, which causes increased strength and contractility of skeletal and cardiac muscle. All these factors contribute to the ill effects of Chocolate Toxicosis on a dog.

References

“Why Chocolate Is Bad for Dogs: Hill's Pet.” Hill's Pet Nutrition, www.hillspet.com/dog-care/nutrition-feeding/is-chocolate-bad-for-dogs.

Gwaltney-Brant, Sharon M. “Chocolate - Toxicology.” Veterinary Manual, MSD Veterinary Manual, May 2013, www.msdvetmanual.com/toxicology/food-hazards/chocolate.

Braeden, Mark. “Why Chocolate Is Bad & Poisonous To Dogs?” Technobark, 11 Apr. 2020, www.technobark.com/why-chocolate-is-bad-poisonous-to-dogs/

“RSPCA Knowledgebase.” Why Is Chocolate Toxic to Dogs and Other Pets?, 9 Nov. 2018, www.kb.rspca.org.au/knowledge-base/why-is-chocolate-toxic-to-dogs-and-other-pets/.