There are a number of foods which should not be fed to dogs. Many of these items appear in human foods as ingredients in whole meals, it is therefore very important to think about feeding scraps from human meals, as there will be hidden foods which should normally be avoided. We strongly advise that you suspect poisoning from foods, you seek veterinarian advice and treatment. As we cannot be certain of the quantities in which the following food items can become harmful for all dogs, we highly recommend that they are avoided fully.

Avocados contain a chemical substance called persin which is an oil-soluble compound. Persin is toxic to dogs when ingested in large amounts. Persin exists in the leaves (the most toxic part), seeds and bark of avocado trees so it may be best to keeps dogs away from avocado trees also.

Onions and Garlic
Onion and garlic in any form is known to destroy red blood cells which can then lead to anemia (and the decreased transportation of oxygen around the cells and tissue of the body). Anemia symptoms include lethargy, breathlessness and very little interest in food overall. Small amounts fed regularly, say cooked in human foods and given to dogs daily, can cause this poisoning. Large amounts can cause more sudden reactions e.g. vomiting.

Raisins and Grapes
Raisins and grapes can cause kidney failure in dogs. Small amounts can cause illness and it is likely you will see lethargy and general weakness along with vomiting. Vomiting repeatedly is an early sign of poisoning.

Caffeine (coffee, tea, soft drinks and chocolate)
Caffeine poisoning can be fatal if a large quantity is ingested. Symptoms of poisoning include general restlessness, shallow and quick breathing, heart palpitations, muscle tremors and fits.

Salt and Sugar
Too much salt can cause extreme thirst and urination which can lead to sodium ion poisoning. Symptoms of too much salt include vomiting, diarrhoea, muscle tremors and raised body temperature. Too much sugar can lead to obesity, dental problems and diabetes.

Milk and Dairy
Generally milk and milk-based products, such as ice-cream or cheese, can cause diarrhoea and digestive upset. It is the lactose (a type of sugar) in the milk which can cause a digestive upset as dogs lack the lactase enzyme which is needed to breakdown the lactose molecules. Abdominal discomfort can follow ingestion of milk and dairy products. Giving lactose free milk and milk-based products may be an option, however, milk is not a nutritional requirement of dogs once their weaned from the mother.

Macadamia Nuts
Ingesting even a few macadamia nuts (raw or roasted) causes illness – it only takes 1-2g of nuts for every kilogram of the dogs own weight to result in poisoning. Vomiting is common, increased heart rate and temperature is also normal following poisoning. In extreme cases, muscle tremors, weakness and paralysis is expected. Dogs can normally return to normal within 24 hours after poisoning, but depending on the quantity consumed veterinarian attention should be sought.

Chocolate contains a substance called theobromine which is a chemical compound found in the cocoa plant. Theobromine is toxic when eaten in large quantities. All kinds of chocolate are a risk food for dogs including dark chocolate, white chocolate and cooking chocolate. All chocolate products should be avoided. Chocolate ingestion causes vomiting, diarrhoea, excessive thirst, muscle tremors, seizures, and death.

Spirits, wine and beer beverages or any foods containing alcohol damages liver and brain cells. It takes much lesser quantities for alcohol to cause damage to cells in dogs than it does in humans. Additionally the size of the dog will be factor in the effects of poisoning also. Alcohol ingestion rapidly causes vomiting and diarrhoea. Depending on the volume of alcohol consumed, the subsequent shut down of the central nervous system leads to decreased coordination, difficulty breathing, coma and death. Dogs do not need to drink much alcohol to die.

Fat and Cooked Bones
Fat trimmed from meat, both cooked and uncooked, can cause pancreatitis in dogs. This includes the skin of poultry. Cooked bones can also splinter and cause obstructions or perforations in the lining of the digestive tract. This can be serious and require surgery to remove or repair. Choking on cooked bones is also common. Uncooked bones a safer option to give as treats.

Raw Eggs and Fish
Raw foods can result in poisoning from bacteria like Salmonella or E. coli if it has been spoiled. Eggs specifically contain an enzyme which interferes with Vitamin B absorption, thus leads to skin problems if chronic. Fish can contain parasites. If the parasites are ingested, disease can develop and can be fatal within two weeks. The first signs of illness are vomiting, raised body temperature and enlarged lymph nodes. Cooking eggs and fish generally kill bacteria and parasites therefore the risk is removed.

Bread Dough

Dough will expand hugely in inside the stomach of a dog after being ingested. As the dough expands, it stretches the stomach wall and causes extreme pain. Additionally as yeast in the bread ferments it produces gas and alcohol. This alcohol has the potential to poison.

Other Miscellaneous Kitchen Items

Many other common kitchen items can be harmful if ingested. For example, baking powder/soda is highly lethal. Certain spices can also be toxic. It is best to keep access to the kitchen limited for the prevention of poisoning (and hygiene).
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