Another potential Christmas food hazard are grapes and their dried fruits (sultanas, raisins and currants). This includes Christmas pudding, Christmas cake and mince pies. Ingestion of grapes or their dried fruits can cause renal failure in dogs but this only happens in a minority of cases. Not all dogs are affected and the reason for this remains unknown. There is also no apparent dose-response relationship. We have follow up information on over 1000 cases of grape and dried fruit ingestion in dogs but only a small number died or were euthanased.
The current understanding is that grape and sultana/raisin/currant toxicity is idiosyncratic and it is still not possible to determine a toxic dose since the risk factors remain unknown. Although it likely that a single grape or piece of dried fruit is unlikely to be a risk, dogs ingesting more than this should ideally receive an emetic and repeat dose activated charcoal.
Owners should be fully informed of the risks and it may be decided to send the dog home after gut decontamination with instructions to return if any signs start, particularly vomiting, at which time IV fluids and bloods for renal parameters are indicated. Certainly, any dog with vomiting and late presentation after ingestion of grapes or dried fruits should be admitted and assessed for kidney injury.