Most people know that chocolate is poisonous to dogs.
It contains a compound called theobromine, and with a large enough dose, this chemical can cause seizures, coma, and even death in dogs. Dark chocolate has far more theobromine than milk chocolate. White chocolate has no theobromine because it’s not really chocolate. Coffee has the same chemical and is also toxic to dogs.
Other foods that are dangerous to dogs include raisins and grapes (both can cause kidney failure), macadamia nuts (they cause weakness, stumbling, vomiting and elevated temperatures), the artificial sweetener xylitol (ingestion of sugar-free gum and other treats causes severe and life-threatening drops in blood sugar and liver failure), garlic and onions (sufficient amounts can cause anemia), and foods that are very high in fat, such as sausage (may trigger a severe bout of pancreatitis).