Grapes, as well as raisins, can cause dogs to have rapid kidney failure. This can even happen without symptoms. This can lead to death in just three or four days.
Rhubarb stalks and leaves both contain oxalate crystals, causing your dog’s calcium to deplete. This can lead to vomiting, diarrhea, weakness, tremors and bloody urine. Leaves contain higher levels of oxalate crystals and are particularly dangerous.
Garlic is a member of the onion family, but is much stronger and more toxic to dogs. In severe cases, ingesting too much garlic might require your dog to have a blood transfusion.