How Much Chocolate is Toxic to Dogs and Cats?

Pinscher mix dog lying by chocolate bar on plate
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Chocolate is dangerous to dogs and cats because of the alkaloid theobromine, which can cause nausea, diarrhea, seizures, racing heartbeat, among more serious complications like heart attack or death. This substance is a stimulant that is in the same family as caffeine.

How Much Chocolate Is Too Much?

The amount of chocolate consumed that may be too much varies widely on the type of chocolate, the size of dog or cat, and how much they have consumed. There are some guidelines and calculators to see how much is too much for each situation. The toxicity levels are the same for cats and dogs.

The toxic dose of theobromine and caffeine for pets is 100 to 200 milligrams per kilogram of the animal, or for every 2.2 pounds that the animal weighs. However, some reports by the ASPCA have noted problems at doses much lower than this like 20 milligrams.

So how does that translate to your dog? If you use the measure of 20 milligrams, which would be when symptoms may start appearing in your dog, then that means a 50-pound dog would need to consume about 9 ounces of milk chocolate to consume about 20 milligrams of theobromine. Some dogs will not appear affected, but some may. This is a much more conservative toxic level calculation than the standard of 100 to 200 milligrams, but better to be safe than sorry.

Perhaps the easiest rule of thumb would be to think that one ounce of milk chocolate per pound of body weight is a potentially lethal dose in dogs and cats.

Types of Chocolate and Levels of Theobromine

Some chocolates are more toxic than others. The sweeter the chocolate, the lesser the theobromine level since theobromine is a bitter substance. Unsweetened baker's chocolate contains eight to 10 times more theobromine than milk chocolate. White chocolate has hardly any theobromine, so theobromine poisoning is highly unlikely if your pet consumes it.

Worse for Dogs?

The toxicity level for either a dog or a cat is the same depending on weight. However, dogs are more so in danger than cats. Dogs have a sweet tooth meanwhile cats do not. A cat may try some chocolate but is less likely to continue eating it.

Calculate Your Pet's Toxicity Level

The bottom line is that a dog or cat sneaking a couple M&M's or Hershey's Kisses shouldn't have a problem, but it isn't a good habit to get into. A chocoholic dog is a potentially disastrous situation. You can try out these chocolate toxicity calculators for an estimate of how much chocolate may be dangerous for your pet.

Medical Treatment for Your Pet

Medical treatment performed by a veterinarian involves inducing vomiting within two hours of eating the chocolate, and the doctor may give the dog medications to control heart rate.

Why Is Chocolate Safe for Humans?

Besides being smaller, an animal's digestive system is different than humans. It takes a much longer amount of time for a dog to metabolize theobromine in the system than a person.