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. In many cases, 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
• Bloating
• Restlessness
• Hyperactivity
• Increased urination
• Drunken gait (ataxia)
• Rigid limbs/muscles
• Tremors
• Seizures
• Rapid breathing
• Abnormal heart rate
• Changes in blood pressure
• Weakness
• Coma

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 40mg/kg of methylxanthines.

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

Therefore, a ten-pound dog would need to ingest more than 80 ounces of white chocolate to experience mild to moderate toxicity, but only about 0.2 to 0.3 ounces (about 6 to 9 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 or call the ASPCA poison control hotline.

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 and should never be attempted if your dogs is already acting sick.

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. In addition, if your dog has ingested a toxic amount of chocolate, additional treatment including intravenous fluids, administration of activated charcoal, and administration of medications to control symptoms such as vomiting, tremors, and elevated heart rate and blood pressure may also be needed. While, it's a good idea to always keep a bottle of unopened, unexpired hydrogen peroxide on hand in case of emergency, it is usually best, to bring your pet directly to your vet unless you are far away and can't get your pet there in time for inducing vomiting to be effective.