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Not an oldwives tale

Chocolate Kills Dogs

Dogs must NOT eat chocolate. Although the reaction to chocolate varies from dog to dog based on the quantity eaten in relation to its size, chocolate is poisonous to dogs and it can be fatal. 

Chocolate contains a chemical called theobromine (a compound similar to caffeine) that is toxic to dogs. Chocolate should be kept away from dogs at all times because they often like and make off with foods that are sweet.

If presented with an opportunity, most dogs will tend to over-consume chocolate. However well trained a dog is, it is still a dog and, like a small child, its curiosity leads it to put things it finds in its mouth. The amount of chocolate that it takes to poison your pet depends on the type of chocolate eaten and the dog’s weight. White chocolate has the least amount of theobromine, at 1 mg per ounce. Baking chocolate or cocoa beans have the highest. Baking chocolate has 450 mg of theobromine per oz; semi-sweet chocolate, 260 mg/oz; milk chocolate, 60 mg/oz; and hot chocolate, 12 mg/oz. Put another way, the ingestion of approximately 24 oz of milk chocolate (a large box of chocolate Valentine’s Day candy or jumbo chocolate Easter bunny) would result in a potentially lethal dose for a 25 pound dog.

Toxicity studies have shown that compared to other species, dogs are unusually sensitive to theobromine. Even small amounts of chocolate can cause adverse reactions that can include nervous system stimulation, tachycardia (fast heart rate), weakness, vomiting and diarrhea, restlessness, irregular heartbeat, hyperactivity, and frequent or uncontrolled urination. These signs usually appear about 4-5 hours after ingestion. Chocolate can also irritate the gastrointestinal tract causing diarrhea and possibly gastric bleeding. More severe signs of chocolate toxicity include tremors, seizures, and death. These symptoms can occur up to two days after the chocolate is eaten. Clinical signs may not appear for several hours after ingestion and complete recovery after veterinary care may take several days. This is because they have a low rate of theobromine metabolism, which causes theobromine to stay in the blood stream for a longer time. After a single dose, the half-life of theobromine in adult dogs is 18 hours, compared to two to six hours in human subjects.

Emergency care for a dog ingesting chocolate includes inducing vomiting and administration of charcoal to reduce absorption of the chocolate remaining in the stomach and intestines. Drugs to stabilize the heart are needed as well as intravenous fluids and drugs to prevent shock. If your pet does accidentally ingests chocolate, consult your veterinarian immediately for advice. The sooner treatment is started the more hopeful the outcome. 

Dangerous Quantities of Chocolate

Dog’s Weight Amount of Milk Chocolate Amount of Unsweetened
Approx. Amount of Theobromide
  5Lbs.    4 oz.   1/2 oz.    200 mg
  10 Lbs.    8 oz.    1 oz.    400 mg
  20 Lbs.    1 Lb.    2 1/2 oz.    900 mg
  30 Lbs.    1 1/4 Lbs.    3 3/4 oz.  1300 mg
  40 Lbs.    2 1/2 Lbs.    4 1/2 oz.  1800 mg
  50 Lbs.    3 Lbs.    5 1/2 oz.  2250 mg
  60 Lbs.    3 3/4 Lbs.    6 3/4 oz.  2700 mg
  70 Lbs.    4 3/4 Lbs.    8 1/2 oz.  3400 mg



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Date Last Updated January, 2006