About Grape and Raisin Poisoning in Dogs

Grape and Raisin Toxicity in Dogs

Grape and raisin (dried grapes) toxicity is well documented in dogs. Although the exact substance that causes the toxic reaction is not yet known, it has been shown that even small amounts of grapes or raisins can prove to be fatally toxic for a dog.

Dogs of any age, breed, or gender may be affected. One of the most serious complications of grape/raisin toxicity is acute (sudden) kidney failure with lack of urine production (anuria). However, kidney failure is not seen in all dogs after ingestion of grapes or raisins, and again, the reason why some dogs are affected excessively while others are not is still being studied. 

Symptoms and Types

• Vomiting and/or diarrhea – often within a few hours; after 24 hours of ingestion vomit and fecal contents may contain pieces of grapes or raisin


• Loss of appetite


• Lethargy, weakness, unusual quietness


• Abdominal pain


• Dehydration


• Oliguria (passing only a small amount of urine)


• Anuria (complete cessation of urine)


• Kidney (renal) failure and death

Causes

Grape and/or raisin ingestion – even small amounts can be toxic for some dogs.

Immediate Treatment

This is an emergency needing immediate treatment. If you are positive that your dog ingested grapes or raisins, you will need to induce vomiting as soon as possible, before the toxins in the fruit can be absorbed.

Try to induce vomiting with a simple hydrogen peroxide solution of one teaspoon per five pounds of body weight – with no more than three teaspoons given at once. If vomiting does not take place within ten minutes of the first administration, you may try again, using the same amount. This method should not be given any more than three times, spaced apart at ten minute intervals.

If your dog has not vomited after the third dose, do not use it, or anything further, to try to induce vomiting. Do not use anything stronger than hydrogen peroxide without your veterinarian’s assent, and do not induce vomiting unless you are absolutely sure of what your dog has ingested. If your dog has already vomited, do not try to force more vomiting.

Also, do not induce vomiting if your dog is unconscious, is having trouble breathing, or is exhibiting signs of serious distress or shock. Whether your dog vomits or not, after the initial care, you must rush it to a veterinary facility immediately.

Activated charcoal is also useful for preventing absorption of toxin. Call a veterinary doctor immediately upon learning of your dog’s ingestion of the grapes or raisins to find out how much activated charcoal to administer to your dog. Keep in mind that you will still need to take your dog in for medical care, as some dogs are more sensitive than others and may need more intensive care, such as a stomach wash/lavage and fluid therapy.

Diagnosis

Your will need to provide your veterinarian with as much information as possible so that treatment can begin. If your dog has vomited or had a bout of diarrhea, and you are able to collect a sample of it, this will help your veterinarian to diagnose the severity of the condition and begin treatment that much more quickly.

Routine laboratory tests, including a complete blood count, biochemistry profile, and urinalysis. These tests may return results of increased blood calcium, which in severe cases can lead to hypercalcemia, and higher than normal levels of phosphorous and creatinine, both indicators of the kidney’s functioning status. Some changes in the urine, like the presence of glucose and/or protein, may be seen.

Ultrasound can also be a useful diagnostic tool for determining the size of the kidney along with finding evidence of abnormal deposition of minerals in the kidneys.

Without explicit evidence of the ingestion (i.e., pieces of the food in the vomit or feces contents), diagnosis is often based on circumstantial evidence along with the usual symptoms that appear after ingestion of grapes and raisins. Often, a toxic substance does not appear on a blood test, as has been the case in previous grape/raisin toxicity cases. The medical research community is continuing work on the discovery of the offending substance.

Treatment

A stomach wash/lavage and fluid therapy are among the first lines of treatment after vomiting has been successfully induced. Intravenous fluid therapy will be given for at least the first 48 hours, and drugs for encouraging urine output will be administered. If urine is not being produced within a short time, your veterinarian may find it necessary to place your dog on dialysis to support the kidneys while they recover. During this time, your doctor will be monitoring your dog’s blood chemicals on a daily basis. 

Once the kidney has failed to the point that urine cannot be produced by the body, the entire system soon follows and the affected animal dies. In some cases, even timely treatment will not be enough if the toxin has already been absorbed. Time is of the essence with this situation, but in all cases, prognosis is guarded.

How to Prevent This Condition

Keep raisins and grapes out of reach of your dog, as dogs will ingest almost anything. Make sure that all family members are aware of the toxic capability of this food, as well as other foods that have been found to be toxic to pets, such as chocolate, onions, garlic, etc. If you do discover that your dog has ingested raisin or grapes, acting immediately is the best prevention for avoiding a complicated situation.