All types of chocolate and cocoa products are dangerous for dogs.
Dark chocolate is the worst.
The toxicity comes from the methylxanthines present in chocolate-based products. These act as a stimulant to the nervous system, cardiovascular system, muscular system and Gastro-intestinal tract.
Grapes and Raisins
Grapes including raisins, sultanas and currants are a no go. Fresh grapes are less toxic than dried fruit. Ingesting these products can cause acute renal failure.
Please remember fruit cake, hot cross buns etc. can also be a problem.
Clinical symptoms often commence with vomiting, diarrhoea and excessive thirst.
Onions and Garlic
It doesn't matter whether they are cooked or raw, it only takes a small amount to cause toxicities in your dog. These plants can damage the red blood cells, leading to anaemia, lethargy and weakness
Nuts and Seeds
Macadamia nuts can cause weakness, vomiting and diarrhoea and pain.
Peanuts can cause vomiting and diarrhoea.
Pistachios are high in fat can cause pancreatitis.