How Much Chocolate Is Toxic to Dogs?

dog and chocolate

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Dog owners usually know that chocolate is poisonous to dogs, but not all understand how much chocolate is toxic and how. As a responsible dog owner, it's important to understand what amount of chocolate is dangerous and proper treatment if your dog eats too much chocolate.

Why Is Chocolate Poisonous to Dogs?

Chocolate can be harmful to dogs for a few reasons. Most commonly, the high-fat content of chocolate and desserts containing chocolate can be enough to cause pancreatitis in dogs. Although there is no exact amount of fat known to lead to pancreatitis, any dog ingesting a sudden large amount of fat is at risk. The danger isn't limited to chocolate either; any food high in fat can lead to pancreatitis. This includes meats, cheeses, and any other high-fat food.

Chocolate itself is toxic because it contains caffeine and theobromine, two chemicals known as methylxanthines. These chemicals can cause problems in dogs that range from mild to severe:

  • Vomiting
  • Diarrhea
  • Increased thirst
  • Enlarged abdomen
  • Restlessness
  • Hyperactivity
  • Increased urination
  • Drunken gait (ataxia)
  • Rigid limbs/muscles
  • Tremors
  • Seizures
  • Rapid breathing
  • Abnormal heart rate
  • Low blood pressure
  • Weakness
  • Coma
  • Heart failure

FYI

Signs of chocolate toxicity typically appear within about six to 12 hours of ingestion. This can vary based on your dog's metabolism and the amount of food and water ingested that day.

How Much Chocolate Is Toxic to Dogs?

For dogs, the toxic effects of chocolate depend on two factors: the level of methylxanthines ingested and the size of the dog. The darker the chocolate, the higher the concentration of methylxanthines. For example, a large breed dog is unlikely to be harmed by eating a bar of milk chocolate. On the flip side, a tiny toy breed may get very sick after eating just a bite of baking chocolate.

Mild to moderate toxic effects of methylxanthines in dogs can appear after a dog ingests as little as 20mg/kg, or 9mg/pound of body weight. Severe effects generally begin to appear when a dog ingests over 50mg/kg of methylxanthines.

The approximate methylxanthine content per ounce of chocolate depends on the type of chocolate:

White chocolate 1.1 mg
Milk chocolate 64 mg
Dark chocolate 150 mg
Semi-sweet chocolate 160 mg
Baking (unsweetened) chocolate 440 mg
Cocoa beans 600 mg
Cocoa powder 807 mg
Cocoa bean hulls 225 mg (Be aware that these may be used for landscaping mulch.)

Therefore, a ten-pound dog would need to ingest about eight or more ounces of white chocolate to experience mild to moderate toxicity, but only about 0.2-0.3 ounces (about 6 to 7 grams) of baking chocolate. Dry cocoa powder is the most toxic, causing toxic effects at as little as 0.14 ounces (4 grams) for a ten-pound dog.

What to Do If Your Dog Eats Chocolate

If you suspect your dog has eaten chocolate, first try to determine the type of chocolate and the amount eaten. Then, call your veterinarian. If it's after hours, try to reach a 24-hour emergency vet in your area.

This chocolate toxicity calculator can help you quickly determine whether or not your dog has eaten enough chocolate to suffer toxic effects. You just need to know your dog's weight along with the type and amount of chocolate eaten. This should be used as a general guideline and not in place of your veterinarian's advice.

If you are unsure whether your dog has eaten enough chocolate to get sick, be sure to contact your vet immediately. No two dogs are the same, so the amounts listed here are all approximations. There is no room for guesswork when it comes to your dog's health.

If your vet thinks your dog has ingested enough chocolate to be poisoned, you might need to induce vomiting. This will not be effective to avoid toxicity if it has been more than about an hour since your dog ate the chocolate.

You may be able to induce vomiting at home using fresh hydrogen peroxide. However, your vet has drugs that can induce vomiting much more quickly and effectively that hydrogen peroxide. It's a good idea to always keep a bottle of unopened, unexpired hydrogen peroxide on hand in case of emergency. Be sure to follow your vet's recommendations regarding the administration of hydrogen peroxide for vomiting. In addition, if you are unable to get your dog to vomit within about 15 minutes, you should get to the nearest open vet office for help.