Harmful Foodstuffs

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Some items in this list require really very large quantities to be ingested before harmful effects show, others can poison very quickly. Many items, such as apples, can be given safely in the sort of treat quantities that might be considered reasonable. If you suspect your dog has been poisoned it is important to seek veterinary advice immediately. You should try and take a sample of what you suspect your dog may have ingested (including vomit if your dog has been sick) to show the vet.


Do not give your dog sips of any alcoholic beverage. Ingestion can lead to injury, disorientation, sickness, urination problems or even coma or death from alcohol poisoning. Some dogs may be attracted to alcoholic drinks - especially milky ones such as white russian or egg nog - so don't leave one sitting where a dog can reach it.  


Acute cases of antifreeze toxicity (when an animal consumes antifreeze) often present as if the animal is intoxicated with alcohol. This is an emergency situation, and life threatening within hours. Please see your veterinarian immediately. Success of treatment depends on quick treatment.  


The seeds contain cyanogenic glycosides which can result in cyanide poisoning in large quantities.  


The seed pit contains cyanogenic glycosides which can cause cyanide poisoning in large quantities.  


Avocado contains a toxic element called persin which can damage heart, lung and other tissue in many animals. Dogs and cats are not severely affected though and the bigger danger in small breeds is likely to be the pip causing choking or an intestinal obstruction.  

Baby Food  

Before feeding any baby food to your dog check the ingredients to see if it contains onion powder, which can be toxic to dogs. Feeding baby food in large amounts may result in nutritional deficiencies.  


Cooked bones can be very hazardous for your dog. Bones become brittle when cooked which causes them to splinter when broken. The splinters have sharp edges that have been known to become stuck in the teeth, caused choking when caught in the throat or caused a rupture or puncture of the stomach lining or intestinal tract. Especially bad bones are turkey and chicken legs, ham, pork chop and veal.

Raw bones (uncooked in any way) like chicken necks or knuckle bones are generally considered safe and help keep your dog's teeth healthy by removing plaque. A caution - bones have a high calcium content and too many can cause severe constipation.  

Bread Dough  

When bread dough is ingested your dog's body heat causes the dough to rise in the stomach. During the rising process alcohol is produced as the dough expands. Pets who have eaten bread dough may experience abdominal pain, bloat, vomiting, disorientation and depression. A pet needs to eat only a small amount to cause a problem, because bread dough can rise to many times its size.  


The toxic ingredient in broccoli is isothiocynate, a gastric irritant. Whilst it may cause stomach upset it probably won't be very harmful unless the amount fed exceeds 10% of the dogs total daily diet.  


Drinks with caffeine (cola, tea, coffee) act as a stimulant and can accelerate your pet's heartbeat to a dangerous level. Pets ingesting caffeine have been known to have seizures, some fatal.

Cat Food  

Cat food is generally too high in protein and fats and is not a balanced diet for a dog. Diarrhoea can quickly be the result of feeding cat food .


The seed pit contains cyanogenic glycosides which can cause cyanide poisoning in large quantities.  


Chocolate contains theobromine, a compound that is a cardiac stimulant and a diuretic. When affected by an overdose of chocolate, a dog can become excited and hyperactive. Due to the diuretic effect, it may pass large volumes of urine and it will be unusually thirsty. Vomiting and diarrhoea are also common. The effect of theobromine on the heart is the most dangerous effect. Theobromine will either increase the dog's heart rate or may cause the heart to beat irregularly. Death is quite possible, especially with exercise. Symptoms of chocolate poisoning include: vomiting, diarrhoea, tremors, hyperactivity, irregular heartbeat and seizures.

Larger quantities of chocolate can poison or even kill a medium or large dog. An ounce or two of chocolate may not seem like much but it can be lethal to a small dog that weighs 10 lbs. or less. After their dog has eaten a large quantity of chocolate, many pet owners assume their pet is unaffected. However, the signs of sickness may not be seen for several hours, with death following within twenty-four hours.

Cocoa powder and cooking chocolate are the most toxic forms. These forms of chocolate contain ten times more theobromine than milk chocolate. Even licking a substantial part of the chocolate icing from a cake can make a dog sick. The next most dangerous forms are semi-sweet chocolate and dark chocolate, with milk chocolate being the least dangerous. A dog needs to eat more than a 250gm block of milk chocolate, however the high amount of fat found in milk chocolate can lead to an attack of pancreatitis.

During many holidays such as Christmas and Easter, chocolate is often accessible to curious dogs and, in some cases, people unwittingly poison their dogs by offering them chocolate as a treat or letting them lick a frosting bowl.  


see Tobacco Products  

Citrus Oil Extracts  

Citrus oil extracts have been known to cause vomiting.  

Corn Cobs  

Many dogs have suffered and, in some cases, died after eating corn-on-the-cob, because the corn cob caused a partial or complete intestinal obstruction. Never allow your dog access to corn cobs.  

Dairy Products  

Most dairy products are digested poorly by dogs who have little or none of the enzyme required to digest the lactose in milk. Just like lactose-intolerant people, lactose-intolerant dogs can develop excessive intestinal gas (flatulence) and may have foul-smelling diarrhoea. It is best to avoid most dairy products altogether, although small amounts of cheese or plain yogurt are tolerated by most dogs, since these products have less lactose than most.  

Food Preparation Items  

When chewing food remnants from aluminum foil, sweet wrappers, paper plates and cups, plastic forks, spoons, knives, roasting bags, meat skewers or binding string a dog may swallow pieces which can cause abdominal discomfort, intestinal blockage, internal bleeding and in some cases, death. There is also a possibility if choking or suffocation. Dispose of food preparation items in a manner that your dog or another animal cannot get to it.  

Eggs (Raw)  

Raw egg whites contain a protein called avidin, which can deplete your dog of biotin, one of the B vitamins. Biotin is essential to your dog's growth and coat health. Additionally, raw eggs are often contaminated with bacteria, such as salmonella, and you could end up giving your dog food poisoning in addition to biotin deficiency.

Symptoms of biotin depletion are hair loss, weakness, growth retardation and skeleton deformity. If your dog is suffering from these symptoms the situation is urgent, and veterinary treatment is needed. Cooked eggs are high in protein and make an excellent treat. It is only the raw eggs that should not be given to your dog.  

Grapes or Raisins  

Although the minimum lethal dosage is not known, grapes and raisins can be toxic to dogs when ingested in large quantities. The symptoms are gastrointestinal signs including vomiting and diarrhoea, and then signs of kidney failure with an onset of severe kidney signs starting about 24 hours after ingestion.  


Spent hops as used in making beer.  


Many dog treats and prepared foods contain liver so it may surprise you to find liver on the bad foods list. In small amounts liver is good for your dog, but if the liver intake is too high it can cause nutritional problems because liver has a high content of vitamin A. Consumption of this vitamin in large amounts can lead to vitamin A toxicity, or hypervitaminosis A. If your dog eats raw liver or consumes three servings of cooked liver a week it could lead to bone problems. Feeding liver to a dog taking Vitimin A supplements can lead to an overdose of Vitamin A.

Symptoms of hypervitaminosis A are deformed bones, excessive bone growth on the elbows and spine, weight loss and anorexia. If left unchecked, hypervitaminosis A has in some cases caused death.  

Macadamia Nuts  

The toxic compound is unknown but eating as few as six nuts without the shell has been known to cause elevated body temperature, accelerated heartbeat, tremors in the skeletal muscles, and weakness or paralysis of the hindquarters. Affected dogs have difficulty or are unable to rise, are distressed and usually panting.Some affected dogs have had swollen limbs and showed pain when the limb was manipulated. Dogs did recover from the muscle weakness and pain and it is not known if there have been any fatal cases. Macadamia butter is included in this warning.  

Mouldy or Spoiled Foods  

The common mold found growing on many foods contain toxins such as Penicillium mold toxins or tremorgenic mycotoxins. Symptoms of poisoning include severe tremors and seizures that can last for hours or even days. This is considered an emergency and medical treatment is needed to control the seizures and detoxify the dog.

Spoiled foods can cause food poisoning. Symptoms of food poisoning are severe vomiting, diarrhoea and shock.

Prevention is the best course, don't feed your dog moldy food left in the refrigerator and don't allow him to raid your garbage cans or compost bin (or your neighbour's).  


Fungi that are poisonous to humans are also toxic to dogs.  


Nutmeg is reported to be a hallucinogen when ingested in large doses. Nutmeg has been known to cause tremors, seizures and in some cases, death.  


Nuts in general are not good for dogs as their high phosphorus content may lead to bladder stones.  


Onions can cause haemolytic anemia, which means that the red blood cells break down leaving the dog short of oxygen. Onion poisoning can occur with a single ingestion of large quantities or with repeated meals containing small amounts of onion. The condition generally improves once the dog is prevented from eating any further onion. The poisoning may occur a few days after the dog has eaten the onion. At first dogs affected by onion poisoning show gastroenteritis with vomiting and diarrhoea, weakness and show little or no interest in food. The red pigment from the burst blood cells appears in an affected dog's urine making it dark colored. The dog will experience shortness of breath because the red blood cells that carry oxygen through the body are reduced in number. Other symptoms are elevated body temperature, confusion, and increased heart rate. Seek veterinary care immediately.

The quantity of onions, raw or cooked, required is high enough that dogs can generally tolerate small doses of onions without any problem and moderate amounts of onion without apparent signs of onion poisoning. All forms of onion can be a problem including dehydrated onions, raw onions, cooked onions and table scraps containing cooked onions and/or garlic. Left over pizza, Chinese dishes and commercial baby food containing onion, sometimes fed as a supplement to young pets, can cause illness.

While garlic also contains the toxic ingredient thiosulphate, it seems that garlic is less toxic and large amounts would need to be eaten to cause illness.  


The seed pit contains cyanogenic glycosides which can cause cyanide poisoning in large quantities.  


The seeds contain cyanogenic glycosides which can cause cyanide poisoning in large quantities.  


Dogs can become extremely ill or even die from eating poisonous plants. Keep all unknown types of plants and any plants suspected of being poisonous out of reach of your pet.

Plastic Food Wrap  

Dogs have been known to ingest pieces of plastic wrap while trying to eat food remnants left on its surface. Plastic food wrap can cause choking or intestinal obstruction. Dispose of plastic wrap in a manner that your dog or other animals cannot get to it.  


The seed pit contains cyanogenic glycosides which can cause cyanide poisoning in large quantities.  


Solanum alkaloids can be found in green sprouts and green potato skins, which occurs when the tubers are exposed to sunlight during growth or after harvest. The relatively rare occurrence of actual poisoning is due to several factors: solanine is poorly absorbed; it is mostly hydrolyzed into less toxic solanidinel; and the metabolites are quickly eliminated. Cooked, mashed potatoes are fine for dogs, and are actually quite nutritious and digestible.  


See Grapes  

Rich Fatty Foods  

Rich, fatty foods can be very dangerous to dogs susceptible to attacks of pancreatitis. Often you may not know that your dog is susceptible until he is very sick with his first attack. It is often the smaller, more energetic breeds like miniature or toy poodles, Cocker Spaniels, Miniature Schnauzers, and other small terrier-type dogs who seem particularly prone. However, any dog may have a problem. It is best to avoid these foods altogether.

Signs of pancreatitis generally include an acute onset of vomiting (sometimes with diarrhoea) and abdominal pain, which may be evidenced as a hunched posture or "splinting" of the abdomen when picked up. The dog may become very sick quickly and often needs intensive fluid and antibiotic therapy.


Iodized salt and salty foods can cause stomach ailments and pancreatitis. Some dogs, especially large breeds, have been known to gulp too much water after eating salty foods and developed a life threatening condition called bloat during which the stomach fills with gas and twists, leading to a painful death unless emergency treatment is received immediately..  

Tobacco Products  

Cigarettes and cigarette ends, cigars, pipe tobacco, nicotine patches, nicotine gum and chewing tobacco can be fatal to dogs if ingested. Signs of nicotine poisoning can appear within an hour and include hyperactivity, salivation, panting, vomiting and diarrhoea. Advanced signs include muscle weakness, twitching, collapse, coma, increased heart rate and cardiac arrest. If anyone who lives in or visits your home smokes, tell them to keep tobacco products out of reach of pets and to dispose of butts immediately. If you suspect your dog has ingested any of these seek veterinary treatment immediately.  

Tomatoes and Tomato Plants  

These contain atropine which can cause dilated pupils, tremors and irregular heartbeat. The highest concentration of atropine is found in the leaves and stems of tomato plants, next is the unripe (green) tomatoes and then the ripe tomato.  


Possibly a surprising inclusion but there are dangers lurking in water that you need to be aware of. Stagnant water may contain harmful bacteria (Leptospira interrogans) and parasites such as giardia. Toilet water with fresheners or cleaners in the tank or bowl contain toxic chemicals.


Xylitol is used as a sweetener. This compound can cause liver damage and death in some dogs.