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Chocolate contains a chemical called theobromine. This chemical is metabolized much slower by dogs, which greatly increases its effects and can even lead to death.
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Dogs are notorious for eating just about anything they deem edible, especially something their people may be eating. Sharing an occasional morsel, such as a little Thanksgiving turkey, with a dog won’t endanger his health.
There is one people food, however, that never should be shared with a dog, and that’s chocolate. In fact, ingesting chocolate is one of the most common causes of food poisoning in dogs.
To avoid a potentially life-threatening situation and an emergency trip to the vet, it’s vital that pet parents keep all chocolate out of their dog’s reach.
Why is chocolate so toxic for dogs?
The methylxanthine alkaloid theobromine is a chemical found in the cacao bean, from which chocolate is derived. It stimulates the cardiovascular system and the central nervous system and it is similar to caffeine.
The main reason that humans can tolerate chocolate while dogs cannot is that dogs and other domestic animals metabolize theobromine much more slowly than do humans. Therefore the chemical accumulates in the body and this greatly increases its effects.
Actually, theobromine can be potentially more dangerous for cats because felines metabolize the chemical even more slowly than do dogs. However, the incidence of chocolate poisoning in cats is much lower because unlike dogs, cats are generally not attracted to sweet foods because they cannot taste sweetness.
Symptoms and health problems
Ingesting even small amounts of chocolate can lead to drooling, nausea, diarrhea and increased urination.
If the animal ingests a toxic amount, however, it could experience hyperactivity, increased blood pressure, internal bleeding, cardiac arrhythmia, tremors, respiratory failure, epileptic seizures, cardiac arrest or even death.
When humans eat chocolate, the theobromine “high” lasts only between 20 and 40 minutes, but in the case of dogs, half the chemical is still in the animal’s system even after 17 1/2 hours.
The clinical symptoms have been known to last for 3 days in the most extreme cases of canine theobromine poisoning.
White vs. dark chocolate
The amount of theobromine varies among different kinds of chocolate. Darker and more bitter chocolate contains more of the chemical.
Baking and cooking chocolate and high-quality dark chocolate can contain up to 450 mg of theobromine per ounce.
An ounce of milk chocolate, however, can contain as little as 44 mg of the chemical. Although there is only about .25 mg of theobromine per ounce in white chocolate, the high concentration of sugar and fat can result in the animal’s developing pancreatitis.
Size matters
Theoretically, a 16-pound dog could die from ingesting a pound of milk chocolate, but a mere ounce of cocoa powder could prove toxic to the same dog.
It would take 5 ounces of dark chocolate but only 1.8 ounces of baker’s chocolate to result in fatality. However, the dog would need to consume 200 pounds of white chocolate to be fatally poisoned!
The degree of theobromine toxicity also depends on the size of the animal. A dog weighing 9 pounds can exhibit signs of theobromine poisoning after ingesting an ounce of baking chocolate or 9 ounces of milk chocolate.
For a 63-pound dog, however, it would take 7 ounces of baking chocolate or 63 ounces of milk chocolate to have the same effect.
If a pet parent suspects their dog has experienced theobromine poisoning, they should contact their veterinarian, who may recommend administering syrup of ipecac to induce vomiting. If the animal begins to exhibit serious symptoms such as hyperactivity, agitation or seizures, an immediate trip to the vet is in order.
