Dangers For Dogs


Some foods commonly enjoyed by humans are dangerous to dogs.


Grapes and Raisins

It has recently been confirmed that grapes and raisins can cause acute kidney failure in dogs.  While as little as one raisin can be toxic to a susceptible ten pound dog, some other dogs have eaten as much as a pound of grapes or raisins at a time without ill effects.  The affected dog usually vomits a few hours after consumption and begins showing signs of renal failure three to five days later.


Dogs love the flavour of chocolate, but chocolate in sufficient doses is lethally toxic to dogs (and horses and possibly cats).  Chocolate contains theobromine, a chemical stimulant.  Dogs are unable to metabolise theobromine effectively.  If they eat chocolate, the theobromine can remain in their blood streams for up to 20 hours, and these animals may experience fast heart rate, hallucinations, severe diarrhoea, epileptic seizures, heart attacks, internal bleeding, and eventually death.


Large breeds are less susceptible to chocolate poisoning, but still are far less tolerant of the substance than humans are.


If you wish to give your dog chocolate treats, buy specially made dog chocolate (with the theobromine removed) from your local pet shop.



Onions contain thiosulfate which causes haemolytic anaemia in dogs (and cats).  Thiosulfate levels are not affected by cooking or processing.  Small puppies have died of haemolytic anaemia after being fed baby food containing onion powder.  Occasional exposure to small amounts is usually not a problem, but continuous exposure to even small amounts can be a serious threat.


Macadamia Nuts

Macadamia nuts can cause stiffness, tremors, hyperthermia, and abdominal pain.  The exact mechanism is not known. Most dogs recover with supportive care when the source of exposure is removed.


Corn on the Cob

Corn on the cob can cause intestinal obstruction in dogs which is a very serious condition.  Corn on the cob should not be fed to dogs.


Cat Food

Cat food should not be fed to dogs due to the higher protein and fat levels.  The nutritional requirements of a cat are significantly different to a dogs.  Likewise, dog food should not be fed to a cat as it lacks taurine which is essential to the health of a cat's heart and eyes.


Alcohol and Hops

Alcoholic beverages pose much the same temptation and hazard to dogs as to humans. A drunk dog displays behaviour analogous to that of an intoxicated person. However, beer presents another problem.  Hops, a plant used in making beer, can cause malignant hyperthermia in dogs, usually with fatal results.  Certain breeds, such as Greyhounds, seem particularly sensitive to hop toxicity, but hops should be kept away from all dogs.  Even small amounts of hops can trigger a potentially deadly reaction, even if the hops are "spent" after use in brewing.


Cooked Chicken Bones

Cooked chicken bones can splinter causing either choking or damage to the dog's mouth. It is the cooking process that makes the bones splinter so easily.



Yeast dough can expand once digested causing pain and problems in the dog's stomach and intestines.



Xylitol is a sugar substitute used in chewing gum, chewable vitamins, candy, toothpaste, and other products. Although empirical studies indicate xylitol may be safe for dogs, there have been cases of foods, candies and gums containing xylitol causing toxic or even fatal liver damage in dogs and should be avoided.


Cows Milk

As with cats, most dogs tend to be lactose intolerant.  A puppy has the enzyme lactase, which breaks down the sugar in milk called lactose.  Once the dog is weaned, he generally stops producing lactase and loses the ability to digest it.  Milk products can then cause an upset stomach and diarrhoea.


Other foods dogs need to avoid are:


Rhubarb leaves

Mouldy and spoiled foods


Tomato leaves and stems

Potato peelings


Some common household chemicals are particularly dangerous to dogs.



Due to its sweet taste, antifreeze poses an extreme danger of poisoning to a dog (or cat) that either drinks from a spill or licks it off its fur.  The antifreeze itself is not toxic, but is metabolised in the liver to a compound which causes kidney failure, and eventual seizures, and death.  By the time symptoms are observed, the kidneys are usually too damaged for the dog to survive so acting quickly is important.

Mouse and Rat Poison

Mouse and rat poison is commonly found in the house or garage.  Dogs readily eat these poisons, which work by depleting stores of Vitamin K in the body, without which blood can not clot properly.  Symptoms of poisoning include depression, weakness, difficulty breathing, bruising, and bleeding from any part of the body.  These symptoms often take 3 to 4 days to show up.  A blood test will show that the blood is not clotting properly.


Zinc toxicity is commonly fatal in dogs where it causes a severe haemolytic anaemia.



If your dog appears unwell and you believe it could be due to something he has consumed, immediately phone your local veterinarian for advice.

Sad Dog