Cocoa beans from which chocolate is made contain alkaloid chemicals called Methylxanthines, specifically caffeine and Theobromine, stimulants which dogs are unable to process in the same way that people do and create the toxicity risk [1].
When people eat chocolate, Theobromine has a half-life of just 6-10 hours as it’s digested and excreted reasonable efficiently, the Caffeine has an even shorter half-life of just 3-6 hours. In the case of dogs, the process is far less efficient, although the caffeine has a half-life not much longer than for people at just 4-5 hours Theobromine remains in the system much longer with a half-life of 17.5 hours meaning dogs are at far greater risk of the toxic effects of these stimulants [2].
Methylxanthines are stimulants which act on both the central nervous, and cardiovascular, systems by blocking the adenosine receptors. Adenosine is an inhibitory neurotransmitter which acts to control or suppress the cardiovascular and central nervous systems, without this control both systems become ‘excited’ or over stimulated to potentially life-threatening levels.
Symptoms of toxicity can range from mild excitability or gastric discomfort such as vomiting and diarrhoea through to hyper excitability, erratic or fast heart rate, seizures and even death [3].
Chocolate comes in many forms, even in the home pantry you could find raw cocoa powder for baking through to biscuits with a little milk chocolate coating. With each variation the Methylxanthines concentration and ultimately potential toxicity varies. Cocoa beans comprise on average 1% Theobromine [4]. Therefore, the more cocoa beans that goes into a chocolate product the more Theobromine or caffeine that final product possesses and the smaller the amount needed to produce toxic effects in the pet. Unsweetened cocoa powder is the most concentrated at 28.5 mg/g followed by baking chocolate at 16mg/g, Dark chocolate at 5.4-5.7 mg/g and milk chocolate at 2.3mg/g [5].
There are various steps involved in treating pets for chocolate toxicity. Firstly, the life-threatening symptoms must be treated such as stabilizing the heart rate with Beta blockers, administering muscle relaxants or barbiturates to alleviate seizures, whilst also managing the pets’ fluid levels and temperature. Once stabilized, gastric irrigation or activated charcoal can be used for any chocolate remaining in the stomach. A catheter can aid in excretion of Methylxanthines by preventing re-absorption across the wall of the bladder. Constant monitoring and adjustment of medication is required to ensure the patient remains stable while the toxins work their way out of the body [5].
Given the severity of symptoms, there is no valid reason to ever feed chocolate to pets and all chocolate products containing any amount of cocoa, no matter how small, should be kept safely out of harm’s way. Personally, I’d recommend the fridge as pet’s, especially dogs, are notorious for getting into bags, drawers and cupboards but I’ve yet to meet one that can open a fridge door without specific training or aids.
Sources
[1] Fernandez, C., 2020. Can Dogs Eat Chocolate? Retrieved November 2nd, 2020, from PetMD web site: www.petmd.com/dog/nutrition/4-types-chocolate-and-how-they-impact-dogs
[2] DeClementi, C., 2011. Chocolate (Proceedings). Retrieved November 5th, 2020, from DVM 360 website: https://www.dvm360.com/view/chocolate-proceedings
[3] Coates, J. , 2012. How Chocolate Makes Dogs Sick. Retrieved November 2nd, 2020, from Pet MD web site and blog: https://www.petmd.com/blogs/nutritionnuggets/jcoates/2012/mar/how chocolate makes dogs sick-13665
[4] Wikipedia., 2020. Theobromine. Retrieved November 6th, 2020, from Wikipedia: https://en.wikipedia.org/wiki/Theobromine
[5] Gwaltney-Brant, S., 2013. Chocolate. Retrieved November 6th, 2020, from msd Vet Manual web site: https://www.msdvetmanual.com/toxicology/food-hazards/chocolate
Comments