Dogs who eat raisins and grapes are at risk for acute and possibly fatal kidney failure. Most dogs will vomit some of the raisins or grapes within hours of eating them, but the damage may already be done. Dogs suffering from grape poisoning stop eating, develop diarrhea, and become quiet with signs of abdominal pain. Eventually the blood calcium levels go up and kidney failure follows. If your dog has eaten raisins or grapes, induce vomiting as soon as you can and take your dog to your veterinarian. He may need to stay for fluid therapy to flush out the toxins. Macadamia nuts are another food that can be toxic to dogs. Dogs who have eaten these nuts will show mild to severe weakness in the rear legs. So far, dogs seem to recover with time, but treating with activated charcoal hastens recovery. Onions have sulfur compounds that can lead to a special type of hemolytic anemia. This does not usually cause acute toxicity signs, but will be picked up on blood work. If your dog has ingested onions, induce vomiting and follow that with activated charcoal. The active yeast in raw bread dough will produce ethanol as the bread rises. This can lead to ethanol poisoning in dogs who ingest it. Unsteady gait and unusual behavior may be the first signs noted. The dog should be taken to your veterinarian, where fluid therapy, along with activated charcoal and possibly the antidote yohimbine, may be administered. Xylitol is an artificial sweetener used by many diabetic people and people who are dieting. Xylitol can cause a dramatic and rapid drop in blood sugar in dogs, and possibly fatal liver damage. If your dog consumes xylitol, even just in sugar-free gum, induce vomiting and contact your veterinarian.