Toxic Raisins
By: Nicole Shalit
Do you feed your dog raisins or grapes? Well stop!
This past week, there was a case of raisin toxicity at MedVet. The patient was a 56 pound, 5-year-old male lab mix who ate half a can of raisins sometime between 7:30 AM and 4:30 PM on Tuesday. The owner noticed the vomiting at first, then came the diarrhea and shaking at about 1:00 AM on Wednesday, however emergency wasn’t called until 7:00 AM. The medics had heard that raisins and grapes were toxic to dogs, but had never witnessed a case before. The emergency clinic gave the dog IV fluids at 1 ½ times maintenance and watched the kidney valves for the next 48-72 hours. The dog’s BUN (blood urea nitrogen level) was 32 when they got to the hospital (normal being less than 27) and creatinine over 5 (1.9 being the higher end of normal). Both of these are monitors of kidney function in the bloodstream. They placed an IV catheter and started the fluids. The renal valves were rechecked at 5:00 PM and the BUN was over 40 and crearinine was over 7; there was no urine production after a liter of fluids. It was then determined that the dog was in acute renal failure, and he was transferred to MedVet to monitor his urine output overnight. Throughout the night he kept vomiting and his renal values have increased daily. The medics were giving him 3 different anti-vomiting medications and his vomiting still couldn’t be controlled. His BUN got to over 120, and his creatinine was at 10 within a few days. His phosphorus was very elevated and his blood pressure (which had been around 150) soared to 220. After days of vomiting, the owners decided to euthanize.
The reason this happens is still unknown, although we have a good idea of the amount a dog would have to consume to become sick. Grapes are estimated at 32g/kg which means grams of grapes per kilograms of mass of the dog. Raisins are estimated at 11-30 g/kg. In some cases, there was an accumulation of an unidentified golden-brown pigment was found with renal epithelial cells.
The symptoms are vomiting and diarrhea. They are often developed a few hours after ingestion. You may even find pieces of raisins and grapes in the stool and/or vomit. Symptoms also include weakness, lack of hunger, increased drinking, and abdominal pain. Acute renal failure will develop within 48 hours of ingestion.
Emesis is usually recommended if the dog is taken to the vet within two hours of the grapes or raisins being eaten. They may also use an emetic such as hydrogen peroxide or apomorphine to make the dogs vomit out the grapes and raisins.