Can lead to renal failure since it believed that dogs cannot metabolize part of the fruit.
Since fruits cannot be broken down, they stay in the gastrointestinal system for a long time. After 12 to 24 hours symptoms of grape or raisin poisoning can include vomiting, diarrhea, anorexia (appetite loss0, abdominal pain, bad breath, diarrhea.
Many of the causes and solutions are described below in the quick reference table and by following the links below: Depends on the type, but usually includes vomiting, diarrhea, hyperactivity, increase urination, hyperthermia.
In chronic cases there can be heart problems, tremors and seizures.
There is no medically determined minimum number of grapes needed to result in toxicity and symptoms. 50% of dogs that ingest grapes or raisins develop no clinical symptoms.