Cocoa powder and cooking chocolate are the most toxic forms of chocolate to a dog. These forms of chocolate contain ten times more toxic ingredients than milk chocolate. Even licking a substantial part of the chocolate icing from a cake can make a dog unwell.
Semi-sweet chocolate and dark chocolate are the next most dangerous forms, with milk chocolate being the least dangerous. Obviously, the smaller the dog, the less it needs to eat.
Onions and garlic are very toxic to dogs. Onions are more of a danger. Dogs affected by onion toxicity will develop hemolytic anemia, where the pet's red blood cells burst while circulating in its body. Symptoms include Hemolytic Anemia, labored breathing, liver damage, vomiting, diarrhea, and discolored urine. The poisoning in dogs occurs a few days after the pet has eaten the onion. 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 puppies, can cause illness.
While garlic is also toxic, it seems that garlic is less toxic and large amounts would have to be eaten to cause illness in dogs.
Raisins or grapes can make a dog ill. Symptoms include vomiting, diarrhea, abdominal pain, and lethargy. If ingested, it can cause liver damage or kidney failure in dogs.
Coffee - Similar to chocolate, a couple of sips of coffee might not harm your pooch, but ingesting coffee grounds, tea bags or energy drinks with high caffeine content can be deadly for them.
Macadamia nuts are another concern, along with most other kinds of nuts. Their high phosphorus content is said to possibly lead to bladder stones. Dogs develop a tremor of the skeletal muscles, and weakness or paralysis of the hindquarters. Affected dogs are often unable to rise and are distressed, usually panting. Some affected dogs have swollen limbs and show pain when the limbs are manipulated.
Other Common Foods that you should avoid feeding your Dog:
1) Mushroom toxicity does occur in dogs and it can be fatal if certain species of mushrooms are eaten. The best thing to do is just don’t give them foods with any mushrooms. Symptoms include abdominal pain, drooling, liver damage, kidney damage, vomiting diarrhea, convulsions, coma, and death.
2) Bones from Fish or Chicken can cause obstruction or laceration of the digestive system. If they get lodged in the intestines, they would need to be surgically removed.
3) Fat Trimmings - Fat trimmed from meat, both cooked and uncooked can cause pancreatitis in dogs. It is also not healthy for them as it promotes weight gain.
4) Raw Eggs or Meat - Contain an enzyme called avidin, which decreases the absorption of a B vitamin. This can lead to skin and hair coat problems. Raw eggs and meat may also contain Salmonella which can result in food poisioning.
5) Milk & Dairy Food - Some adult dogs and cats do not have sufficient amounts of the enzyme lactase, which breaks down the lactose in milk. This can result in diarrhea. Lactose-free milk products are available for pets.
6) Baby Foods - Some baby foods contain onion powder, which can be toxic to dogs. Although most baby food without onion or garlic is fine, baby food should only be used for a short time since it is low in nutritional value for dogs.
7) Raw Fish - Can result in a B vitamin deficiency leading to loss of appetite, seizures, and in severe cases, death. More common if raw fish is fed regularly.
8) Cat food - Although not toxic, the two kinds of foods are designed to be different nutritionally. Cat foods are generally high in protein and fats and not suitable for a dog’s diet.