Onions and Garlic

 Keep onions and garlic -- powdered, raw, cooked, or dehydrated -- away from your dog. They can kill his red blood cells, causing anemia. That's eventhe onion powder in some baby food. A rare small dose is probably OK. But eating a lot just once or can cause poisoning. Look for signs like weakness, vomiting, and breathing problems. 

Coffee, Tea, and Other Caffeine

 Give your dog toys if you want him to be perky. Caffeine can be fatal.  Watch out for coffee and tea, even the beans and the grounds. Keep your dog away from cocoa, chocolate, colas, and energy drinks. Caffeine is also in some cold medicines and pain killers. Think your dog had caffeine? Watch for restlessness, fast breathing, and muscle twitches. 

Grapes and Raisins

 There are better treats to give your dog.  Grapes and raisins can cause kidney failure in dogs. And just a small amount can make a dog sick. Vomiting over and over is an early sign. Within a day, your dog willget sluggish and depressed. 

Thanks 

source 

http://pets.webmd.com/