Has your dog ever gotten into a piece of chocolate cake you had sitting on the counter for dessert? Have you ever wondered whether you need to head to the hospital when the last piece of your chocolate bar goes missing? People tend to think that chocolate is deadly for dogs, and while it can be for some, it actually depends on a few different factors: the size of the dogs, the amount and type of chocolate consumed, and the dog's age and overall health.
What Makes Chocolate Toxic?
Chocolate is made from cacao seeds, or beans, and they contain theobromine and caffeine, which are bitter chemical compounds that can have detrimental physiological effects on dogs. These effects include stimulating the nervous system and speeding up the heart rate, which can also cause restlessness, vomiting, diarrhea, seizures, and even death. Dogs actually metabolize theobromine significantly slower than humans do. Humans tend to feel the effects of chocolate for about twenty to forty minutes after consuming it, while dogs will still have half of the theobromine in their system after seventeen hours.
In addition to the theobromine and caffeine content, the weight of the dog has a significant effect on the toxicity levels. It varies greatly, but the idea is that any amount of chocolate is going to have a stronger negative effect on a small dog rather than a larger one. Effects can appear within six to twelve hours after consuming, but they can last up to three days.
The strength of the chocolate, or the percentage of pure cacao in the chocolate, is another primary factor that impacts the level of toxicity of chocolate consumption in dogs. A typical bar of mass-produced milk chocolate consists of 11% cacao—but a bar of fine bean-to-bar milk chocolate may consist of up to 50% or so of cacao. A well-known brand of what is labeled “super dark” chocolate is 34% cacao, whereas other dark chocolates go all the way up to 100% cacao (Tangle Chocolate is 70% cacao). So in order to accurately decide whether your dog has eaten too much chocolate, you really need to know the percentage of cacao, not just whether it is labeled “milk,” “dark,” “super dark,” or something else.
What’s Safe and What’s Not?
The chart below illustrates how the dog’s weight, the amount of chocolate consumed, and the percentage of cacao determine whether your dog could be in danger from eating too much chocolate. A simple way to think about it is a dog can consume one ounce of mass-market milk chocolate per pound of body weight.
Ounces of Chocolate Required to Produce Toxicity in Dogs
|
Weight of Dogs |
|
Type of Chocolate |
10 lbs |
20 lbs |
30 lbs |
40 lbs |
50 lbs |
60 lbs |
|
Mass-Produced Milk Chocolate, such as Hershey’s Milk Chocolate Bar (11% cacao, typically 1.5 oz) 1 oz/pound |
10 oz |
20 oz |
30 oz |
40 oz |
50 oz |
60 oz |
|
70% Dark Chocolate .14 oz/pound |
1.4 oz |
2.8 oz |
4.2 oz |
5.6 oz |
7 oz |
8.4 oz |
According to this chart, Tangle Chocolate's official dog, Sierra, could eat 40 Hershey bars before getting sick compared to 5.6 equivalent-sized 70% dark chocolate bars. It is highly unlikely that Sierra could consume that much of either kind!
The Experts Weigh In
A vet who wanted to remain anonymous mentioned that “it’s really about the caffeine in the chocolate” that affects the dogs. The caffeine makes them get all hyped up, causing them to run around the house like they are having a heart attack. They need to be “forced to throw up, and then put on an IV” for hours in order to get it out of their system. According to this vet, chocolate toxicity among dogs is not terribly common, but it is not rare either. This vet sees “one dog every couple or three weeks” in his very busy practice that comes in with chocolate toxicity.
Another vet, Kathy Osborne of Northampton, Massachusetts stated, “People come in and want to know exactly how much chocolate is too much. There isn’t a clear answer, because every dog seems to process the chemicals in chocolate a little bit differently, and every kind of chocolate is made differently, which affects how the chemical gets absorbed. Also, the age of the dog plays a part, because in general, a liver in a young dog will process toxic chemical compounds better than a liver in an old dog. And your dog’s heart health also needs to be considered. The most serious effects of chocolate have to do with the heart and the nervous system, so if your dog has a history of heart disease or seizures and has eaten chocolate, you should seek immediate medical attention. I have never actually known a dog who died from eating chocolate...they tend to vomit it up if they’ve really overdosed...but it’s in the literature, so it does happen.”
Just a bite?
Understanding and learning about the effects of certain types of chocolate can be useful when deciding whether or not you need to take your dog to urgent care. Eating a single crumb of a chocolate donut, or a piece of the chocolate brownie you have been saving off the counter, should not affect your dog. But, if your dog has eaten chocolate and doesn’t look completely normal, we suggest that you pick up your phone, call your vet, and get more information from an expert who knows your dog best.
https://www.medicinenet.com/pets/dog-health/facts_on_dogs_and_chocolate.htm
https://www.petmd.com/dog/chocolate-toxicity
Interviews with two Veterinarians