How Much Chocolate is Dangerous for Dogs?

A lot of pet owners know that chocolate is a no-go but don't really know the reason it's bad for them—or how much chocolate is dangerous for dogs.

Why Chocolate Is Toxic for Dogs

Here's the scoop: Chocolate contains two compounds—caffeine and theobromine—that can cause life­ threatening heart or breathing problems in dogs. Signs of toxicity typically appear within 6 to 12 hours of ingestion and may include abnormal thirst, restlessness, hyperactivity, tremors, seizures and rapid breathing. (Chocolate is also high in fat, which may lead to gastrointestinal distress like vomiting or diarrhea, though this is less likely to be serious.)

The holidays are a particularly tricky time of year to keep sweets away from your four-legged friend. Not only is chocolate likely to be more abundant in homes, you may also be less vigilant about making sure your canine can't get his paws on it during this busy time of year. (Think: the box of chocolates put on the coffee table for guests or a batch of brownies left to cool a little too close to the edge of the counter.) Your best defense is to be alert to these risks and store treats out of reach—but accidents can happen.

What to Do if Your Dog Eats Chocolate

Whether you need to rush to the vet depends on the type of sweet and the size of your dog. White chocolate contains minimal amounts of the toxic compounds, milk chocolate has moderate levels and dark or bittersweet chocolate has the most.

Dog Chocolate Calculator

Find out here how much chocolate is dangerous for your dog with this calculator.

Large dogs can also tolerate more chocolate than small ones before it becomes a big concern. (This doesn't mean it's OK to feed big dogs chocolate, only that you probably don't need to panic if he eats a few morsels.) An 80-pound Labrador, for instance, would have to eat at least 4½ standard milk chocolate bars (at 1.55 ounces each) before it could be toxic—though the same amount of dark chocolate would likely be an emergency.

On the other hand, a tiny pooch—­under 10 pounds—can only tolerate the equivalent of one Hershey kiss. Of course, when in doubt, seek emergency veterinary care.