Why Is Chocolate Bad For Dogs?

Question

You always hear that chocolate is bad for dogs but never why. I have had several dogs and all have eaten chocolate and nothing ever occurred. So what is the mystery behind chocolate being bad for dogs? Is it really true or just a myth?

Answer 1

"Most pet owners realize that chocolate is bad for dogs, yet few could tell you what makes chocolate poisonous, or just how much is toxic to a dog. The truth is that chocolate contains theobromine, a compound in the same family as caffeine and theophylline. Dogs metabolize this class of drugs differently than humans. Once ingested, theobromine stays in the dog's body a long time. Too much of it can cause illness and even death.

The good news is that it takes a fairly large amount of theobromine (100 – 150 mg/kg of body weight) to cause a toxic reaction in a dog. The bad news is that some forms of chocolate do contain a large amount of this substance, with unsweetened baking chocolate being the most dangerous.

Related Resources on Common Foods that are Toxic for Dogs:
The American Society for the Prevention of Cruelty to Animals offers quite a bit of information about foods that are toxic to animals. Included is an article from Veterinary Technician magazine about the recently-discovered danger in grapes and raisins. It is definitely worth a read...
On average:

Milk chocolate contains 44 mg/oz
Semisweet chocolate contains 150 mg/oz
Unsweetened baking chocolate contains 390 mg/oz
Therefore, a toxic dose of chocolate would equate to:

1 oz per pound of body wt. for milk chocolate
1 oz per 3 lbs. of body wt. for semisweet chocolate
1 oz per 9 lbs. of body wt. for unsweetened baking chocolate
So, although it would cause major digestive problems, a 16 lb. dog would probably have to eat a whole 1 lb. bag of milk chocolate Hershey's kisses to reach a toxic level of theobromine. However, just 2 oz. of dark baking chocolate would cause great risk, and perhaps be fatal, to that same 16 lb. dog.

To some people, the numbers may imply that it's OK to give their dog a small amount of milk chocolate on occasion. The danger lies in the fact that the dog will certainly develop a “taste” for chocolate, and go after even the bitter types of chocolate that are dangerous in small amounts.

The following are signs of theobromine overdose:

hyperexcitability and restlessness
Gastro-intestinal distress (vomiting and diarrhea)
increased heart rate and cardiac arrhythmia
increased urination
muscle tremors
seizures, coma, death

There is no specific antidote for theobromine poisoning, although activated charcoal may be used to absorb the toxin from the stomach. Hydrogen peroxide can be used to induce vomiting, however this should not be attempted without instruction from a veterinarian. If a dog has eaten an undetermined amount of chocolate, contact a vet immediately. And warn people to think twice before ever offering their canine a taste. Even if he happens to be a Chocolate Lab."

Answer 2

Theobromine poisoning or chocolate poisoning is an adverse reaction to the alkaloid theobromine, found in chocolate, tea, cola beverages, and some other foods. Cacao beans contain about 1.2% theobromine by weight, while processed chocolate generally has smaller amounts. The amount found in highly refined chocolate candies (typically 40-60 milligrams per ounce or 1.4 to 2.1 grams per kilogram) is much lower than that of dark chocolate or unsweetened baker's chocolate (over 400 mg/oz or 14 g/kg).

The amount of theobromine found in chocolate is small enough that chocolate can be safely consumed by humans in large quantities, but animals that metabolize theobromine more slowly can easily consume enough chocolate to cause chocolate poisoning. The most common victims of theobromine poisoning are dogs (for which it can be fatal). Cats and especially kittens are yet more sensitive, and many other animals are also susceptible.

The first signs of theobromine poisoning are nausea, vomiting, diarrhea, and increased urination. These can progress to cardiac arrhythmias, epileptic seizures, internal bleeding, heart attacks, and eventually death.

Theobromine is especially toxic to horses, dogs, parrots, voles, and cats because they are unable to metabolize the chemical effectively. If they are fed chocolate, the theobromine will remain in their bloodstream for up to 20 hours. Medical treatment involves inducing vomiting within two hours of ingestion, or contacting a veterinarian.

A typical 20 kg dog will normally experience intestinal distress after eating less than 240 g of dark chocolate, but won't necessarily experience bradycardia or tachyarrhythmia unless it eats at least a half a kilogram of milk chocolate. According to the Merck Veterinary Manual, approximately 1.3 g of baker's chocolate per kilogram of a dog's body weight (0.02 oz/lb) is sufficient to cause symptoms of toxicity. For example, a typical 25 gram baker's chocolate bar would be enough to bring out symptoms in a 20 kg dog.

Answer 3

It has a substance called theobromine in it, which causes increased urination and also causes problems with the central nervous system. Dogs can eat only 1oz per pound of body weight of milk chocolate and be ok...while bakers chocolate they can only eat 1oz per 10lbs of body weight...If your dog does eat chocolate he can become overexcited, hyperactivity, vomitting and diarrhea...In severe cases it can cause hypothermia, muscle tremors, seizures, and sometimes death. White chocolate is the least worrysome of all of the chocolates while baker's chocolate is the worst.

Answer 4

Yeah, the theobromine is bad news for dogs. Our vet said that dark chocolate has the most theobromine in it and not to give any of that to our dogs.

I asked my vet about this because I was sharing chocolate with my brother's dog and he about had a cow. He starts yelling at me and asking me what do I think I'm doing---am I trying to kill his dog?

I just looked at him, I didn't know what to say. When he and I were kids I had a german shepard and she was my best friend. I shared everything with her--soda, chocolate, gum, wax candy with the juice in it. I don't know how much of all that she liked--I think a lot of it was liking it because I was eating it.

Hmmmm, come to think of it, my brother would never share his chocolate with her! He was a greedy little boy.

Anyway---I asked my vet about it and he said that chocolate was bad for dogs. I still give my dogs an M&M every now and then. They'd like the whole bag---but I just give them one or two. They enjoy it and I don't think that's enough to hurt them. I don't share any of my dark chocolate with them though----even though they do beg like monkeys for it.

Answer 5

Got this from www.dogownersdigest.com

Why is Chocolate Lethal?
Chocolate contains theobromine. A naturally occurring stimulant found in the cocoa bean, theobromine increases urination and affects the central nervous system as well as heart muscle. While amounts vary by type of chocolate, it's the theobromine that is poisonous to dogs.

Symptoms of Chocolate Dog Ingestion and Poisoning
You can recognize that your dog has eaten a toxic dose of chocolate from the symptoms. Within the first few hours, the evidence includes vomiting, diarrhea or hyperactivity. As time passes and there's increased absorption of the toxic substance, you'll see an increase in the dog's heart rate, which can cause arrhythmia, restlessness, hyperactivity, muscle twitching, increased urination or excessive panting.

This can lead to hyperthermia, muscle tremors, seizures, coma and even death.

How Much Chocolate Is Deadly?
If a 50-pound dog eats a teaspoonful of milk chocolate, it's not going to cause serious problems. However, if that same dog gorges himself on a two-layer chocolate cake, his stomach will feel more than upset and soon it's likely he'll be vomiting or experiencing diarrhea.

To answer the question "How much is too much" is not simple. The health and age of your dog must be considered. Obviously if your dog is aged and not in top shape, his reaction to a plate of chocolate is going to be different from a young healthy dog of the same weight.

Another fact that must be considered is this: Not all chocolate is the same. Some has a small amount of theobromine; another type has a large amount and still another contains an amount that is somewhere in between. The quantity has a relationship with the weight of your dog. Small dogs can be poisoned, it is easy to understand, from smaller amounts of theobromine than large dogs.

Which chocolate is the safest, relatively speaking? White chocolate. It has the least amount of theobromine: 1 mg per ounce. Far on the other side of the spectrum is baking chocolate, which has a huge 450 mg of theobromine per ounce!

Here are a few other chocolates for you to ponder: hot chocolate, 12 mg of theobromine per ounce; milk chocolate, 60 mg/oz; and up there near baking chocolate: semi-sweet chocolate with 260 mg/oz.

You might try using this to remember these chocolates from least to most toxic: What Happy Moose Says BAA? Or: White-Hot-Milk-Semi-Baked. If you have a better way to remember, contact us!

Knowing which chocolate is the most toxic is important, but leaves one wondering how much must be eaten to poison a dog. The list in this box should be helpful. Maybe you can clip it and post it on your refrigerator?


White chocolate: 200 ounces per pound of body weight. It takes 250 pounds of white chocolate to cause signs of poisoning in a 20-pound dog, 125 pounds for a 10-pound dog.
Milk chocolate: 1 ounce per pound of body weight. Approximately one pound of milk chocolate is poisonous to a 20-pound dog; one-half pound for a 10-pound dog. The average chocolate bar contains 2 to 3 ounces of milk chocolate. It would take 2-3 candy bars to poison a 10 pound dog. Semi-sweet chocolate has a similar toxic level.
Sweet cocoa: 0.3 ounces per pound of body weight. One-third of a pound of sweet cocoa is toxic to a 20-pound dog; 1/6 pound for a 10-pound dog.
Baking chocolate: 0.1 ounce per pound body weight. Two one-ounce squares of bakers' chocolate is toxic to a 20-pound dog; one ounce for a 10-pound dog.

Answer 6

Its true that chocolate is bad for dogs. They are allergic to something in the coco in the chocolate. If you give them too much it can kill them but your dogs have probably been alright because you haven't given them much.

Answer 7

Because many dogs have an alergy to chocolate. I have a standard poodle that loves chocolate and even jumps up on the counter and opens the cabinet to get it!!! Fortunately he is not alergic or he would probably be dead by now!

Answer 8

Honey, it's not a myth, if I were you - I'd quit giving my dogs chocolate.

Answer 9

For one it will get diarrhea and it will make the dog hi per just like it does kids

Answer 10

its a myth that CHOCOLATE is bad for dogs, but the CAFFIENE is really bad for them, also caffiene reletives. the caff it makes ther heart pump so fast it literally explodes. most candy bars w/ milk chocolate are OK, also i knew a dog who ate four fudge pies in a row and she was fine. I love chocolate :( :| :) :D