Death by Chocolate

Chocolate Toxicity

It takes a fair amount of chocolate to kill a pet, but chocolate can be toxic.  It contains a xanthine compound called theobromine.  Caffeine is another xanthine compound.

The toxic dose of theobromine is about  70 mg per pound of pet, but like many substances, it all depends on the sensitivity of the patient.

Milk chocolate contains 6 mg of theobromine per ounce. Semi-sweet chocolate contains about 22 mg/oz. and baking chocolate about 350 to 400 mg/oz.

I did have a small dog who ate a large candy bar die early on in my practice but since then I've had lot's of calls where sypmtoms were just mild GI upset, but xanthines affect  the central nervous system, the cardiovascular system and peripheral nerves. 

Symptoms include hyperexitablility, hyper irritability, increased heart rate, increased urination, vomiting and muscular tremors or seizures.

Making the pet vomit is helpful if it's within an hour or so of ingesting the chocolate and giving an absorbent like activated charcoal might help, but the main part of treatment for chocolate intoxication involves treating the symptoms: controlling seizures, heart arrthymias, intestinal spasms and diarrhea, and supportive therapy like Oxygen and IV fluids.  This is a job for your vet.

Cocoa Mulch, which is sold by Home Depot, Foreman's Garden Supply and other
Garden supply stores contains a lethal ingredient called "Theobromine". 

It is lethal to dogs and cats.  It smells like chocolate and it really attracts dogs.  They will ingest this stuff and die.  Several deaths already occurred in the last 2-3 weeks.  Just a word of caution -- check what you are using
in your gardens and be aware of what your gardeners are using in your

Theobromine is the ingredient that is used to make all chocolate --especially dark or baker's chocolate -- which is toxic to dogs. 

Cocoa bean shells contain potentially toxic quantities of Theobromine, a xanthine
compound similar in effects to caffeine and theophylline. 

A dog that ingested a lethal quantity of garden mulch made from cocoa bean shells developed severe convulsions and died 17 hours later. 

Analysis of the stomach contents and the ingested cocoa bean shells revealed the presence of
lethal amounts of Theobromine.

Grapes and Raisins

This week I had the first case in history of raisin toxicity ever seen at MedVet. My patient was a 56 pound, 5 yr old male neutered lab mix who ate half a canister of raisins ometime between 7:30 AM and 4:30 PM on Tuesday. He started with vomiting, diarrhea and shaking about 1 AM on Wednesday but the owner didn’t call my emergency service until 7 AM.
I had heard somewhere about raisins AND grapes causing acute renal failure but hadn’t seen any formal paper on the subject. We had her bring the dog in immediately. In the meantime, I called the ER service at MedVet, and the doctor there was like me—had heard something about it, but…. Anyway, we contacted the ASPCA National Animal Poison Control Center and they said to give I V fluids at 1 1/2 times maintenance and watch the kidney values for the next 48-72 hours.
The dog’s BUN (blood urea nitrogen level) was already at 32 (normal less than 27) and creatinine over 5 (1.9 is the high end of normal). Both are monitors of kidney function in the bloodstream. We placed an I V catheter and started the fluids. Rechecked the renal values at 5 PM and the BUN was over 40 and creatinine over 7 with no urine production after a liter of fluids.

At the point I felt the dog was in acute renal failure and sent him on to MedVet for a urinary catheter to monitor urine output overnight as well as overnight care. He started vomiting again overnight at MedVet and his renal values have continued to increase daily. He produced urine when given lasix as a diuretic. He was on 3 different anti-vomiting medications and they still couldn’t control his vomiting.

Today his urine output decreased again, his BUN was over 120, his creatinine was at 10, his phosphorus was very elevated and his blood pressure, which had been staying around 150, skyrocketed to 220. He continued to vomit and the owners elected to euthanize.

This is a very sad case—great dog, great owners who had no idea raisins could be a toxin. Please alert everyone you know who has a dog of this very serious risk.

Poison control said as few as 7 raisins or grapes could be toxic. Many people I know give their dogs grapes or raisins as treats. Any exposure should give rise to immediate concern.
Laurinda Morris, DVM
Danville Veterinary Clinic
Danville, Ohio

Xylitol Toxicity:

Xylitol is a sugar alcohol that is used in sugar-free products such as gum and candy, as well as for baking and is used in the production of certain low-carbohydrate products now on the market.  Xylitol is becoming more and more common in food products in the U.S.

As early as the 1960's, experiments indicated a link between the ingestion of xylitol and hypoglycemia in dogs. However, it has only been recently that the ASPCA Animal Poison Control Center has begun to receive reports of xylitol toxicosis in dogs. It is believed that this recent rise is likely due to the increased use of products containing xylitol in the United States.

Effects of Xylitol Ingestion

In both humans and dogs, the levels of blood sugar are controlled by the body's release of insulin from the pancreas. In human xylitol ingestion does not cause any significant changes in insulin levels or, therefore, blood glucose. However, in dogs, xylitol causes a fast release of insulin, which results in a rapid decrease in blood glucose (hypoglycemia).

Clinical Signs

Clinical signs of xylitol toxicity can develop in as few as 30 minutes after ingestion. Clinical signs may include one or more of the following:

* Vomiting
* Weakness
* Ataxia (uncoordinated movements)
* Depression
* Hypokalemia (decreased potassium)
* Seizures
* Coma
* Liver dysfunction and/or failure


After ingesting a xylitol-containing product a dog may receive one of more of the following treatments, depending on the amount of time that has lapsed since the ingestion occurred. The induction of vomiting is recommended if performed very soon after ingestion of the xylitol-containing product but before clinical signs develop. Frequent small meals or an oral sugar supplement may be used to manage dogs that have not yet shown clinical signs. Following the appearance of clinical signs intravenous dextrose can be used to control hypoglycemia. It may also be necessary to treat the patient for low potassium levels (hypokalemia), if indicated. Treatment should be continued until the blood glucose levels return to normal levels.

What's On This Page:

The dangers of pets eating chocolate, raisins, onions, garlic, turkey skin, grapes,
Cocoa bark, nuts, green potatoes, artificial sweetners.  This is a first draft so please be patient

On Other Pages

This is a first draft... please be patient

Cocoa Mulch

Cocoa bean shells are a by-product of chocolate production (which is how mulch made it into the "foods" category) and are popular as mulch for landscaping. Homeowners like the attractive color and scent, and the fact that the mulch breaks down into an organic fertilizer. However, some dogs like to eat it and it contains Theobromine.

Fatty foods

Fatty foods are hard for a dog to digest and can can overtax the pancreas, leading to pancreatitis. This can threaten your dogs health and is potentially fatal.


Macadamia nuts should be avoided. In fact most nuts are not good for a dogs health since their high phosporus content is said to lead to bladder stones.


Mulch isn't food, but there's one type tempting enough for dogs to eat. Some dogs are attracted to cocoa mulch, and will eat it in varying quantities. The coca bean shells can contain from 0.2% to 3% theobromine (the toxin ) as compaired to 1-4% in unprocessed beans.


Onions, especially raw onions, have been shown to trigger hemolytic anemia in dogs. (Stephen J Ettinger, D.V.M and Edward C. Fieldman, D.V.M. 's book: Textbook of Veterinary Internal Medicine vol. 2 pg 1884.) Stay away from onion powder too.


Potato poisonings among people and dogs are rare but have occurred. The toxin, solanine, is poorly absorbed and is only found in green sprouts (these occur in tubers exposed to sunlight) and green potato skins. This explains why incidents seldom occur. Note that cooked, mashed potatoes are fine for a dogs health, actually quite nutritious and digestible.

Artificial Sweeteners

Xylitol is used as a sweetener in many products, especially sugarless gum and candies. Ingesting large amounts of products sweetened with xylitol may cause a sudden drop in blood sugar in dogs, resulting depression, loss of coordination, and seizures. According to Dr. Eric K. Dunayer, a consulting veterinarian in clinical toxicology for the poison control center, "These signs can develop quite rapidly, at times less than 30 minutes after ingestion of the product" states Dr. Dunayer, "...therefore, it is important that pet owners seek veterinary treatment immediately."


Turkey skin is currently thought to cause acute pancreatis in dogs, partly due to it's high fat content.

Other foods listed by the ASPCA as harmful:

Alcoholic beverages

Avocado (the only "fatty" member of the vegetable family)

Coffee (all forms of coffee)

Moldy or spoiled foods


Yeast dough


Foods That Are
Sometimes Poisonous
to Cats & Dogs