Onions are toxic to dogs and can cause gastrointestinal and blood problems. Symptoms may not appear immediately.
Chocolate is toxic to dogs and can cause kidney failure. Dark chocolate is the most dangerous.
Macadamia nuts are toxic to dogs and can cause weakness, swelling, and panting.
Corn on the cob can be fatal to dogs. The cob can cause a blockage in the intestines.
Avocados are toxic to dogs and can cause vomiting and diarrhea.