Grape/Raisin Poisoning in Dogs

Dogs of any age, breed or gender can be affected by raisin and grape toxicity.

Alison Laurie-Chalmers, Senior Consultant, Crown Vets Inverness

Grapes and raisins are a poisonous threat to dogs. Currently it is not known why these fruits are toxic to dogs. Some researchers suspect that a mycotoxin, a toxic substance produced by a fungus or mould may be the cause. Some suspect that a salicylate type (aspirin-like) drug may be naturally found in the grape.

With Easter almost here, hot cross buns do pose a poisoning risk to dogs. The raisins, currants and sultanas contained in these sweet treats can be highly toxic to dogs and eating them can lead to kidney failure and even death. On top of this, nutmeg which is also a common ingredient in hot cross buns is also potentially dangerous to dogs. This is due to it containing a hallucinogenic toxin called myristicin which can cause a mild stomach upset even if eaten in small doses. Dogs who eat large amounts of nutmeg may suffer more severe symptoms such as increased heart rate, disorientation, abdominal pain, hallucinations and even seizures. These symptoms can last up to 48 hours.

All grapes, raisins, currants and sultanas and any foods containing these can be poisonous to dogs, and potentially poisonous to cats, with the dried versions of these fruits more frequently associated with severe symptoms. Ingestion of even a small amount can lead to toxicity, so any exposure should give cause for concern. It is unclear exactly what causes these toxic effects, but just one grape, raisin, currant or sultana can be potentially toxic, so real caution should be taken with these fruits and any foods that contain them.

Among the most common clinical symptoms recorded in dogs after eating these fruits were loss of appetite, sickness, diarrhoea, lethargy, weakness and abdominal pain once the toxins are absorbed.

Normally any symptoms start showing between six and 24 hours after the dog has eaten grapes or raisins. These symptoms may not take effect for several days and in the most serious cases the fruits can also cause sudden kidney failure.

The prognosis for grape and raisin toxicity is generally good if patients are treated very early on and there has been no kidney damage. Patients are treated by inducing vomiting and administering activated charcoal and fluid therapy. The goal is to avoid or block absorption of toxins and prevent or minimise damage to the patient’s kidneys.

Do keep all these fruits or foods containing these well out of reach of your pets. If you think your dog has eaten grapes, raisins, sultanas or currants, or any foods containing them, do not wait for any signs or symptoms to appear, you should telephone the practice immediately to ensure that appropriate treatment can be given to induce vomiting before any toxins are absorbed.