There have been reported cases of grape and raisin toxicity in dogs. No particular toxin has been identified yet, but reports of dogs eating grapes, grape casings after the grapes have been pressed and raisins have caused problems. No other species of animals have been reported to have similar problems.
The amount of reported ingestion to cause a toxic reaction in dogs ranges from 3 grams to 57 grams per kilogram of body weight (do I need to reference my sources?).
So, if we estimate about 80 green grapes per pound, in the case of your Yorkie, which is probably 5 to 6 pounds, that equates to eating as few as three grapes or as many as thirty to cause a toxic reaction. So I wouldn´t risk giving such a small dog any grapes at all, especially since the range of toxicity is rather wide.
Some of the effects of grape or raisin poisoning are in the gastrointestinal tract and the kidneys. Initially there can be vomiting and lethargy, you can tell he doesn´t feel well. These signs usually develop within hours of eating the grapes or raisins. Also, loss of appetite, diarrhea and abdominal pain, have been reported. In dire cases, acute kidney failure can occur within 24 to 72 hours after ingestion, with death occurring in 50–75% of the dogs with acute renal failure. To treat a suspected case of grape or raisin poisoning, your dog must be treated aggressively to prevent kidney failure.
So don´t risk giving grapes or raisins to tiny dogs! Stick to the tried and true treats!
Sharon E. Anderson, DVM
