Chocolate and Dogs - A Deadly Combination!

by Jeanine Dunaj, RPh

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.

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.

Jeanine Dunaj is a registered pharmacist licensed in Michigan. She is also a free-lance writer and editor of the Elixir Capsule. Copyright © 2004 Jeanine Dunaj, RPh, all rights reserved. First appeared in the Elixir Capsule, the newsletter of Elixir pc, Temporary Pharmacy Staffing