cincinnati dog pages Kathy McRoberts

Is Chocolate Really Bad for Dogs?

You’ve probably heard it before… don’t give chocolate to your dogs because it’s bad for them. Well, with Valentine’s Day coming up, I thought I’d explore that statement in more depth.


Chocolate is made from the fruit (bean) of the tropical cacao tree. It goes through an extensive process to turn the bitter bean into the smooth, yummy chocolate we all love. All chocolate is made essentially of cocoa liquor (the liquefied cocoa) and cocoa butter extracted from the bean. Much of the commercial chocolates also contain sugar and sometimes milk, milk powder and vanilla. There are several substances that occur naturally in cocoa, including caffeine and theobromine, known as alkaloids. It is the theobromine that makes cocoa toxic to animals, particularly dogs, horses and cats.

Unlike humans, dogs’ systems cannot metabolize the theobromine present in chocolate, it is absorbed into the bloodstream and remains present for much longer (up to 20 hours). Small amounts of theobromine can cause vomiting, diarrhea, excessive urination, thirst and nervousness. At higher levels the animal may experience muscle spasms, seizures and even death.

How much chocolate is dangerous? Well, that depends on several factors including the type of chocolate ingested, and the size of the dog.

Chocolate comes in several forms, varying in the amount of cocoa. Usually the darker the chocolate the more cocoa it contains, which means more theobromine.

White Chocolate contains an insignificant source of theobromine since it is made of cocoa butter and milk and sugar, but no cocoa liquor.
Chocolate Bars Milk Chocolate = 44-64 mg of theobromine per ounce
Semisweet or Dark Chocolate = 150-160 mg/oz
Unsweetened Baking Chocolate = 450 mg/oz
Dry Cocoa Powder = 800 mg/oz

So as you can see, the darker the chocolate, the more poisonous it is to dogs. The size of the animal also contributes to the amount of toxicity. The toxic dose of theobromine is considered to be approx. 100-200mg for every 2.2 pounds of body weight. However, the ASPCA has noted problems at doses as low as 20 mg for every 2.2 pounds of body weight.

Now that you are totally confused, here is an easy way to gauge how much chocolate is poisonous to your dog.

Toxic Amounts of Chocolate:
White Chocolate: generally safe
Milk Chocolate: 1 oz. per pound of body weight
Semisweet or Dark Chocolate: 1 oz. per 3 pounds of body weight
Unsweetened Baking Chocolate: 1 oz. per 9 lbs. of body weight

A typical candy bar is 2-3 ounces. Therefore a 50 pound dog may be able to eat a few milk chocolate bars without much upset, but one square of baking chocolate could kill a Chihuahua or small dog.

Each dog is different and many dogs experience problems at much lower levels than this, this is only a guide. The best advice is to keep all chocolate away from your dogs at all times. Though a few M&M’s or a stray chocolate chip on the floor might not be a problem, once your dog gets a taste of chocolate they will want more and it may be hard to keep them away from it. So keep all chocolate out of reach and in sealed containers to be safe.

Symptoms of chocolate poisoning in dogs include excitement, nervousness, trembling, vomiting, diarrhea, and excessive thirst and/or urination. If you notice any of these symptoms within 12 hours after ingestion of chocolate, contact your vet immediately. If you cannot reach your vet, contact a local emergency veterinary clinic. Use the link to the left to contact the Pet Poison Helpline for assistance. Treatment by a vet may include IV fluids, inducing vomiting, activated charcoal, anti-seizure medications, or cardiac medications.

An interesting side note: Ever hear of cocoa bean mulch used in gardens? Apparently it is a good choice for a garden mulch, it is made from cocoa bean shells. However, many people report that this mulch is potentially dangerous to dogs because it contains a high amount of cocoa and thus a high amount of theobromine. There have been reports of dogs eating the mulch in large amounts resulting in death. The toxicity of the mulch has not really been proven, but you might want to choose a different type of mulch to use if you own dogs. As they say, better safe than sorry.

By the way, chocolate is just as dangerous to cats, but due to their eating habits and less of a “sweet tooth” they normally aren’t overly interested in chocolate.

The Pet Poison Helpline reports that chocolate poisoning is the number one type of poisoning they receive calls about. So this Valentine’s Day, keep some yummy dog treats handy and keep the chocolate safely tucked away from your canine companion.

Sources:—”Chocolate”,—”Chocolate Toxicity and Pets”,—”Theobromine Chemistry”,—”Chocolate Poisoning in Dogs” by Kevin Fitzgerald,—”Why is chocolate dangerous for dogs to eat”,, ASPCA, Pet Poison Helpline