While we as humans have little-to-nothing to worry about when it comes to gobbling down a handful of grapes or raisins, the same cannot be said for our dogs. As pet owners, it is important for us to know which types of foods are safe and which could be dangerous or potentially fatal if our animals happen to eat them. One item to add to your list of non-friendly food items are grapes as well as their prunier counterpart, the raisin. If you have ever wondered, “is it okay if my dog ate raisins?”, then this blog post is for you.

It has been found that grapes, raisins and even currants (some currants are actually small, black grapes) have been well-documented as being toxic for dogs and therefore should be avoided as best as possible. It is unclear whether this is a new problem, or if the toxic nature of grapes and raisins became recognized after the establishment of a computerized animal toxicity database about 25 years ago. Whatever the case may be, the number of identified cases of illness or death in dogs after they have eaten raisins or grapes is on the rise.

Ingestion of even a small amount of grapes, raisins, or currants can result in severe, acute canine kidney failure. All types of grape- or raisin-containing products (including grape juice, trail mix, bagels, etc.) can result in this condition. Poisoning has occurred in dogs after eating a variety of grape-related items such as seedless or seeded grape varieties, commercial or homegrown fruits, red or green grapes/raisins, organic or non-organic fruits, and grape pressings from wineries. Even the organic, pesticide-free, grapes grown in home gardens can result in toxicity. Although pinning down exactly what it is within raisins that causes the toxic reaction is not yet known, it is still a good idea not to let your dog eat them just in case. Because even the smallest amount of this fruit can end up being a serious problem and fatally toxic for your canine. All in all, watch out for the raisin!

Symptoms of Raisin Toxicity

Dogs of any age, breed, or gender can be affected by a series of unfortunate problems if they happen to consume grapes or raisins. The toxic agent within grapes/raisins has not yet been identified but appears to be associated with the flesh of the fruit. In other words, peeled and/or seedless grapes are still considered toxic. The reason this pint-size fruit is so bad for dogs is that it can cause serious complications for them such as severe kidney damage which can lead to sudden kidney failure and lack of urine production.

Most cases of grape and raisin poisoning are diagnosed because an owner knows or suspects that their dog has eaten the fruit. Sometimes partially-digested grapes and raisins can be seen in a dog’s vomit or fecal matter. Routine laboratory tests, including a complete blood count, biochemistry profile, and a urinalysis, can help to diagnose most cases of acute kidney failure regardless of the cause.

The toxicity is also not necessarily dose-dependent, and symptoms can occur with even small ingestions. Some researchers suspect that a mycotoxin (a toxic substance produced by a fungus or mold) may be the cause. Some suspect a salicylate (aspirin-like) drug may be naturally found in the grape, resulting in decreased blood flow to the kidneys. However, so far no toxic agent has been identified. And since it is currently unknown why these fruits are toxic, any exposure should be a cause for concern. Although there are two principles that seem to prevail when it comes to this affliction:

1. Dogs are more likely to become poisoned if they ingest large amounts of fruit.
2. There is significant individual sensitivity amongst dogs.

Kidney failure is not seen in all dogs after ingestion of grapes or raisins as each dog’s system is unique and is affected differently by certain things. Ingesting even the smallest amount of a grape or raisin can be toxic for some dogs while other dogs can ingest relatively large amounts without developing any of the obvious symptoms. There is no way to predict which dogs may be more sensitive and finding out why some dogs are affected excessively, while others are not, is still being studied.

Unfortunately, the symptoms of grape or raisin poisoning are non-specific and are similar to kidney failure from many other causes. Your veterinarian will base a presumptive diagnosis of this poisoning on a history of eating grapes, raisins, currants, or the presence of pieces of grapes or raisins in the dog’s vomit. Your veterinarian will also recommend diagnostic tests such as a complete blood count (CBC), a serum biochemistry profile, and a urinalysis to assess the amount of damage to the kidneys. These test results will help determine the dog’s likelihood of recovery.

In general, grape and raisin poisoning will usually cause dogs to develop some combination of the following symptoms:

• Vomiting and/or diarrhea – often within a few hours of ingestion. Vomit and fecal contents material 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)
• Foul breath
• Oral ulcers
• Tremors
• Seizures
• Coma

Immediate Treatment

If you suspect that your pet has eaten any of these fruits, please contact your veterinarian or Pet Poison Helpline, an animal poison control service, immediately. You do not want to waste any time! Since there are still many unknowns associated with this type of poisoning in dogs, it is better not to take any chances when it comes to your pet’s health. The goal of treatment is to block absorption of the toxins and prevent or minimize damage to the kidneys. The best treatment is to decontaminate your animal right away via the induction of vomiting and administration of activated charcoal. This will help to prevent absorption of the toxin from the stomach or intestines. As with any toxin, the sooner the poisoning is diagnosed and treated, the less harm is expected for your pet, as well as reducing the amount of worry and stress for you.

When treating a dog who has eaten grapes or raisins, if you go to a veterinarian, they will start by inducing vomiting (if the ingestion has occurred within the last two hours and the dog hasn’t already vomited) possibly followed by gastric lavage (washing out the stomach) and administration of activated charcoal to absorb any remaining toxins. After this, your vet will begin intravenous fluid therapy to flush the toxins out of the dog’s bloodstream and to encourage the kidneys to keep producing urine. If necessary, the veterinarian will give your dog medications to reduce vomiting and maintain kidney function. During this time, the doctor will be monitoring your dog’s kidney function with regular rechecks of bloodwork.

Ideally, dogs should be hospitalized on intravenous fluids for 24-to-48 hours following ingestion. Affected animals may need to be hospitalized for 2-7 days. During the course of treatment, your veterinarian will monitor the patient’s kidney values daily to assess the dog’s response to treatment and determine whether the treatment needs to become more aggressive. Blood work should also be repeated 2-3 days after going home; this is to make sure the kidney blood values have not increased. Drugs to control canine nausea or vomiting, to help maintain blood flow to the kidneys, and to control blood pressure will be administered as indicated.

Grape/Raisin Toxicity is an emergency, needing immediate treatment. So if you are positive that your dog ingested grapes or raisins within the last two hours, and you don’t have time to run to the vet, then you will need to induce vomiting as soon as possible, before all the toxins from the fruit can be absorbed.

However, do not attempt to induce vomiting if your dog is:

• Unconscious
• Is having trouble breathing
• Is exhibiting signs of serious distress or shock
• Or if you are unsure of what your dog may have eaten.

If your dog has already vomited, do not try to force them to vomit again. Call your veterinarian for advice. If they recommend that you induce vomiting at home, use the following method:

• If the dog has not eaten within the last two hours, offer him a small meal. This makes it more likely that the dog will vomit.
• Measure 1 milliliter (ml) of 3% hydrogen peroxide per pound of the dog’s weight, using either a syringe (without a needle) or teaspoon (one teaspoon is approximately five ml). The maximum amount of hydrogen peroxide to be given at any one time is 45 ml, even if a dog weighs over 45 pounds.
• Squirt the hydrogen peroxide into the back of the dog’s mouth using the syringe or you can try a turkey baster if a syringe is not handy.
• If vomiting does not take place within fifteen minutes of the first administration, you may try again, using the same amount. This method should not be used more than two times and should be spaced apart in fifteen-minute intervals.

If your dog has not vomited after the second dose of hydrogen peroxide, do not continue to use it, or anything else, to try to induce vomiting. You do not use anything stronger than hydrogen peroxide in your dog without first talking to your veterinarian. And whether your dog vomits or not, after you’ve provided the initial care, you must rush them to a veterinary facility immediately. Your veterinarian may need to perform a gastric lavage and/or administer activated charcoal to deal with any toxins that remain in your dog’s stomach, as well as institute treatment to protect your dog’s kidneys.

Prognosis

Prognosis of toxicity depends on many factors, including how severe the poisoning was, how soon your pet was decontaminated, whether or not they already have developed kidney failure, how soon treatment was initiated, and whether or not their clinical signs and kidney values improved once treatment was started.

If a dog only ate a few grapes or raisins (depending on their size, of course) and received immediate treatment, the prognosis for recovery can be quite excellent. However, as the poisoning progresses, the kidneys may shut down and if the kidneys are damaged to a point where urine is no longer being produced, and your dog’s blood pressure starts to increase dramatically, your dog will usually lapse into a coma. If a dog’s kidneys have failed to the point that they can no longer produce urine, the prognosis becomes grave and the likelihood of a turnaround is not very good and fatality is sadly more likely to happen.

The kidneys have very little capacity to regenerate or repair themselves so once they are damaged, they will not function as well as they did before the incident occurred. When in doubt, seek treatment right away by contacting your veterinarian or Pet Poison Helpline for advice. Your veterinarian will be able to estimate the prognosis for your dog based on described symptoms, the individual situation at-hand, and response to treatment. Hemodialysis may be necessary to support life until (and if) the kidneys can recover. Kidney transplant may also be an option for some owners, but in most cases, euthanasia is the only practical option once a dog’s kidneys have totally shut down.

Prevention

There are a few simple things you can do to help your dog avoid developing toxicity from consuming these foods:

1. Keep raisins and grapes out of your pet’s reach, as dogs will ingest almost anything that crosses their path.
2. Make sure that all family members are aware of the toxic capacity of this food, as well as other foods that have also been found to be poisonous to pets, such as chocolate, onions, garlic, etc.
3. If you do discover that your dog has ingested grapes or raisins, acting immediately gives your dog the best chance at survival.