Grapes and raisins are the most dangerous common fruits for dogs, capable of causing fatal kidney failure even in small amounts. But they’re far from the only risk. Several everyday fruits contain toxic compounds, sharp pits, or seeds that can poison or physically harm your dog. Here’s what you need to know about each one.
Grapes and Raisins
Grapes and raisins are the single most dangerous fruit a dog can eat. Ingestion causes acute kidney injury, and the toxic compound has recently been identified as tartaric acid, a naturally occurring acid found in the fruit’s flesh. Just 200 grams of grapes (roughly a cup and a half) contains about 2.4 grams of tartaric acid, which is enough to seriously harm a medium-sized dog.
There is no established “safe” amount. Some dogs develop kidney failure after eating just a few grapes, while others eat a larger quantity and show milder symptoms. This unpredictability makes any amount dangerous. Tartaric acid concentrations vary between grape varieties and even between growing seasons, so you can never assume a small exposure is harmless.
Symptoms typically appear fast. Most dogs develop vomiting or diarrhea within 6 to 12 hours of eating grapes or raisins. Without treatment, kidney failure can set in within 24 to 72 hours. Once the kidneys stop producing urine, the prognosis becomes very poor. Raisins are actually more dangerous by weight than fresh grapes because drying concentrates the tartaric acid. Tamarind fruit carries a similar risk.
Stone Fruits: Cherries, Plums, Peaches, and Apricots
The flesh of most stone fruits is not toxic to dogs in small amounts, but the pits, leaves, and stems contain compounds that release cyanide during digestion. If a dog crushes or chews through a pit, the cyanide interferes with the body’s ability to use oxygen at the cellular level, which can cause rapid decline.
Signs of cyanide poisoning include difficulty breathing, bright red gums, dilated pupils, excessive drooling, tremors, and difficulty standing. In severe cases, dogs can collapse or have seizures. These symptoms can progress quickly, so any dog showing breathing changes or disorientation after eating stone fruit needs emergency care immediately.
Even when the pit isn’t crushed, whole pits pose a choking hazard and can cause intestinal blockage, especially in smaller dogs. If your dog swallows a plum or peach pit whole, watch for vomiting, loss of appetite, or straining to defecate over the next day or two.
Avocado
Avocado is more nuanced than most people realize. The leaves, skin, and pit contain a fungicidal toxin called persin, which is highly toxic to birds and horses but far less dangerous to dogs. Dogs are relatively tolerant of persin and would typically need to consume large quantities of the skin or leaves to experience poisoning. The flesh itself is considered safe in small amounts.
The real danger with avocado is the pit. It’s large, round, and smooth, making it easy for a dog to swallow and nearly impossible to pass. A swallowed avocado pit can lodge in the throat or intestines, creating a blockage that may require surgery. If you share avocado with your dog, remove the skin and pit completely and keep portions small.
Citrus Fruits
Lemons, limes, grapefruits, and oranges contain essential oils and compounds called psoralens, concentrated mainly in the skin, pith, and seeds. The flesh of these fruits is generally safe for dogs in small quantities, though most dogs dislike the taste anyway. The ASPCA lists lemon trees as toxic to dogs due to the oils and psoralens in the plant material and skins.
A dog that eats citrus peel or chews on citrus plant leaves may develop vomiting, diarrhea, and lethargy. Skin contact with the oils can also cause irritation. A wedge of orange flesh won’t hurt your dog, but whole citrus fruits left on the ground (especially from backyard trees) can be a problem if your dog chews them up rind and all.
Starfruit
Starfruit is one of the less commonly discussed but genuinely dangerous fruits for dogs. It contains high levels of oxalic acid, which can cause acute kidney damage, along with a neurotoxin called caramboxin. In research on rats, caramboxin caused seizures when applied directly to brain tissue, even in preparations where all oxalate had been removed, confirming it has independent neurotoxic effects.
The likely sequence of harm works like this: the high oxalate load damages the kidneys first, and as kidney function drops, the neurotoxin accumulates in the body because it can no longer be filtered out. This can produce hiccups, confusion, and seizures. The soluble oxalate concentration in starfruit ranges from 80 to 730 milligrams per 100 milliliters, which is quite high. Large amounts, or even smaller amounts eaten on an empty stomach, increase the risk. Dogs with any existing kidney problems are at particular risk, but even dogs with healthy kidneys can be affected.
Green Tomatoes
Ripe red tomatoes are fine for dogs in small amounts, but green (unripe) tomatoes and the stems and leaves of the tomato plant contain solanine and related compounds called glycoalkaloids. These affect both the nervous system and the digestive tract. Estimated toxic levels range from 0.1 to 1.0 percent of a dog’s body weight, consumed as green plant material. For a 20-pound dog, that could be as little as an ounce of green tomato plant.
Symptoms include drooling, vomiting, diarrhea, loss of appetite, tremors, weakness in the hind legs, and general lethargy. At very high doses, glycoalkaloid poisoning can progress to paralysis and unconsciousness. If you grow tomatoes in your yard, fence off the garden or keep your dog away from the plants, since the green parts are the most concentrated source.
Persimmons
Persimmon flesh is not chemically toxic to dogs, but the seeds and skin create a real physical hazard. The seeds can cause intestinal blockage, particularly in small and medium dogs, because they don’t break down easily during digestion. A blockage can lead to vomiting, loss of appetite, abdominal pain, and inability to pass stool. Severe cases may require surgery. If you have a persimmon tree and your dog has access to fallen fruit, monitor them closely during fruiting season.
What to Do If Your Dog Eats a Toxic Fruit
Call your veterinarian or a local emergency veterinary clinic immediately. Be ready to tell them what fruit your dog ate, roughly how much, when they ate it, and your dog’s approximate weight. This information helps the vet determine how serious the situation is and what to do next.
Don’t try to make your dog vomit without professional guidance. Inducing vomiting is sometimes the right move, but in other situations it can make things worse, especially if the dog ate something with sharp pits or if too much time has passed. Your vet will decide whether vomiting should be induced and may administer activated charcoal to reduce absorption of the toxin.
If you can’t reach your vet, call the ASPCA Poison Control Hotline at 888-426-4435 or the Pet Poison Helpline at 855-764-7661. Both are available 24/7 and can walk you through first aid steps while you arrange to get your dog to a clinic. With grape or raisin ingestion in particular, speed matters: treatment within the first few hours dramatically improves the odds of a full recovery.