Can Cats Eat Grapes?

You might have heard of the concerns about dogs eating grapes and started to wonder whether cats can eat grapes. Fortunately, most cats have little to no interest in sharing our fruit snacks. As obligate carnivores, cats simply aren’t wired to eat much in the way of sugary fruits or carbs. But is it safe if your cat eats a grape that falls on the floor?

Here’s what you need to know about cats and grapes.

Are Grapes Bad for Cats?

Grape toxicity is uncommon in cats, but it has been documented. Approximately 15% of dogs and cats that eat grapes or raisins will show signs of toxicity—they become restless, have a reduced appetite, and begin to vomit. In one study, less than 1% (and all were dogs) later had kidney damage. However, cases of kidney damage in cats after eating grapes or raisins have been documented, so we know it can happen, just not very often.

The toxin has not yet been identified, but since both seedless and seeded grapes have been involved, we believe the toxin is not in the seeds. The current thought is that it is a water-soluble compound in the flesh of the grape. Some evidence has been given to show that tartaric acid may be the cause, and this is found in different concentrations in grapes and raisins.

Can One Grape Hurt a Cat?

It is difficult to figure out how many grapes or raisins may be safe since some animals seem to be able to eat them freely without any complications. However, the lowest amount known to have resulted in kidney damage for grapes is 0.7 oz per 2.2 pounds of the pet’s weight, and for raisins, the amount is 0.11 oz per 2.2 pounds.

There are approximately four grapes in an ounce (depending on the size of the grape, of course) so a 10-pound dog or cat could get sick from eating as few as 12 grapes. There are approximately 60 raisins in an ounce, so the toxic threshold would be as few as 30 raisins for a 10-pound animal.

Raisins are nothing more than dehydrated grapes, which concentrates all of the “stuff” in the grape, so in theory, they are more toxic than the grapes themselves in small quantities.

What To Do if Your Cat Has Eaten Grapes

If your cat has eaten grapes—or even just a single grape—it’s best to call a veterinarian immediately because, although rare, the consequences of acute kidney disease are extremely concerning. This is a situation where time is important, as significant damage can occur in a very short period of time.

The safest way to handle the situation is to call your veterinarian (or an emergency clinic) immediately if your cat has eaten ANY grapes at all. They will best advise you whether any home care is needed and will likely recommend that you contact poison control.

If your cat may have eaten several grapes, bring them immediately to the nearest veterinary hospital for care. Do not induce vomiting unless the veterinarian has recommended that you do so. It’s easy to cause more damage than good when trying to get a cat to vomit.

Signs of Grape Poisoning in Cats

The initial signs of grape poisoning that may be seen within the first 12-24 hours of eating the fruit include:

• Lethargy or weakness

• Vomiting

• Diarrhea

• Decreased appetite

• Abdominal discomfort

Over the next 24 hours (48 hours after ingestion), you may see more dramatic signs of kidney disease, including:

• Excessive thirst and urination

• More significant nausea and vomiting

• No appetite

• Strong-smelling breath

• Neurologic signs, which can progress to seizures and coma

Ideally, cats should be treated for grape ingestion right away, but within the first 12 hours, some of the kidney damage may still be preventable. Once kidney damage occurs, it is often no longer fully reversible.

How Vets Treat Grape Toxicity in Cats

Most veterinarians will do a thorough physical examination on any cat that has eaten grapes, carefully taking note of their vital signs and any discomfort, particularly around the kidneys. Baseline blood and urine will be sampled, which is very helpful for comparisons over the next hours and days. Animal poison control may be consulted to help make a thorough diagnostic and treatment plan based on your cat’s particular circumstances.

In most cases, veterinarians will try to decontaminate your cat’s intestinal tract by causing vomiting and using a binding agent to try and absorb any toxins left in the system. They will also try to flush the bloodstream and kidneys using IV fluids, which keeps the urine flow high, aiming to help protect the kidneys from the toxic agents.

The vet will check your cat’s blood work repeatedly while they are in the hospital. If the kidneys are not showing signs of damage, many cats can go home after 24-36 hours. However, if the kidneys have been injured, longer stays are possible. In this case, there are often long-term medications that will need to be given at home, but this will depend on the degree of damage that has been done.

Although it is extremely uncommon for cats to eat grapes, and rare for them to become sick from them, if they do develop kidney damage because of the grapes, it can be fatal. Until we know more, it is best to keep grapes and raisins out of reach and to let your veterinarian know if your cat does eat any grapes.

Featured image: iStock.com/IRYNA KAZLOVA