As a dog owner, I’ve always been told to not let your dog have chocolate because it is poisonous for them to eat. Well, a question that I’ve had for years is “How much chocolate can a dog eat before it has a health problem?”

My curiosity finally got the best of me (I must be a cat) and I decided to do some research on the topic of dogs and chocolate. I have to be honest:  I was a bit surprised by the information I found.

The following information is from the November 2012 “Your Dog” newsletter written by the Cummings School of Veterinary Medicine at Tufts University.

As it turns out, it is not the chocolate that is the potential problem; it is a caffeine-like chemical found in chocolate called theobromine that is the troublemaker. Theobromine can cause symptoms in a dog that are similar to those we can experience during a major caffeine overdose.  Symptoms include:  agitation, hyper-excitation, and possible seizures.

However, as you can read in the table below, the size of your dog and the type of chocolate they get into are major factors in determining the impact of that “stolen” chocolate snack on your pet!  For example, if you have a 30-pound dog and they “steal” an 8-ounce milk chocolate candy bar, they should be okay unless they are diabetic or have other health issues.

How Much Chocolate is Toxic?

Dogs Weight Toxic Amount of Milk Chocolate Toxic Amount of Dark Chocolate

5 pounds

4 ounces

0.5 ounce

10 pounds

8 ounces

1.0 ounce

20 pounds

1.0 pound

2.5 ounces

30 pounds

2.0 pounds

3.25 ounces

40 pounds

2.5 pounds

4.5 ounces

50 pounds

3.0 pounds

5.5 ounces

60 pounds

4.0 pounds

7.0 ounces

70 pounds

5.0 pounds

8.5 ounces

80 pounds

6.0 pounds

10.0 ounces

100 pounds

8.0 pounds

13.0 ounces

120 pounds

10.0 pounds

1 pound

On the other hand, if you have a small dog, that 8-ounce chocolate candy bar that went missing can be a real problem!  In my case, my dog, Sienna, weighs 12 pounds and my daughter loves dark chocolate so I know there is going to be dark chocolate around the house.  A few dark chocolate Kisses lying around where Sienna can get them could turn into a major problem!

So, be very careful if you have chocolate treats, especially dark chocolate, around the house and you have dogs “running” around!

Other potential problem foods for your dog include onions and garlic. Both of these foods can cause hemolytic anemia (destruction of red blood cells) in your dog.  As with chocolate, while it is better to keep these items out of your dog’s reach, your canine friend would need to eat a “large” amount of onion or garlic to become sick.

However, what you do need to be extremely careful about is making sure your dog never gets into any grapes or raisins, both of which are associated with kidney failure in dogs!  Even just a few may be enough to make your dog ill.

As always, if you have any questions about your pets, contact your local veterinarian for answers.


 ‘Your Dog – The Newsletter for caring dog owners.’ Written by Cummings School of Veterinary Medicine at Tufts University; November 2012, Vol. XVIII, Number 11.

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