Toxic for dogs – list of toxic substances

Dogs are often experts at eating things they shouldn’t. It is also not easy to keep track of what is dangerous and what is not. Some substances can be life-threatening even if only very small amounts are consumed, while others are only toxic in large quantities. Here we list some of the things that can cause poisoning in your dog.

Dog chewing on carrot.

What is poisonous to dogs?

Rat and Mouse Poisons (Rodenticides)

Rat and mouse poison contains substances that impair the blood’s ability to clot. If your dog has ingested rat poison, it can lead to internal bleeding. This condition can be life-threatening.

Therefore, be vigilant when you walk your dog in places where it is possible that rat poison is laid out. Rat poison is palatable and is attractive for pets to eat. The biggest risk is that curious dogs ingest the poison directly, but they can also be affected if they eat mice or rats that in turn have ingested the poison.

If you suspect that your pet has ingested rat poison, contact your vet immediately. Your vet will need to know what type of rat poison was consumed by your pet so keep the packaging. Some types of poison are more harmful than others. The vet will also want to know how much poison was consumed and how long ago it was eaten and approximate weight of your dog. Do not wait for symptoms to appear before seeking veterinary attention. If your pet attends a vet very soon after eating the rat poison, the vet can induce vomiting and reduce the chances of your pet digesting the poison.

Symptoms: Bleeding from the nose, oral cavity and throat. Bruises, internal bleeding, coughing, blood in faeces, etc. Can lead to death.


Pain tablets intended for humans should never be given to dogs except on the direct recommendation of a veterinarian, e.g., paracetamol (Panadol/Calpol). The dosage differs between humans and dogs and therefore needs to be determined by a veterinarian. Never give your dog ibuprofen (Nurofen). If you suspect that your pet is in pain, is sick or has a fever you will need to bring your dog to the vet. The vet will prescribe medication that is suitable for your pet if necessary.

If you suspect that your pet has consumed pain killers or anti-inflammatories intended for human use, contact your vet immediately. You will also need to seek veterinary advise if your dog has inadvertently ingested an overdose of painkillers/anti-inflammatories that has been prescribed by the vet. It is important not to wait for your dog to become sick before seeking veterinary attention as your pet is at a very high risk of developing irreversible and life-threatening kidney and liver damage.

It is likely that your vet will induce vomiting if the medication has been consumed recently. Your pet may need hospitalisation with supportive IV fluids and blood tests to evaluate organ function.</pZ

It is important to keep all human and veterinary medication out of reach of your pets.

Symptoms: Diarrhoea, vomiting, bloody or black tarry stools, abdominal pain, swelling of face, limbs or neck, pale gums, jaundice, laboured breathing, depression, excessive thirst, dark urine.


Antifreeze (ethylene glycol) is a highly toxic chemical. It is contained in coolant and washer fluid. Unfortunately, it is frequently ingested by dogs and cats as it is sweet and pleasant tasting. Antifreeze poisoning is often fatal as it causes kidney failure. If you suspect that your pet has ingested even a tiny amount of antifreeze, take your pet to the vet immediately. Your pet may not show signs of ethylene glycol poisoning until a few days after ingestion by which time kidney failure will have developed. The quicker your pet is treated after ingestion the better chance your pet has at survival. It is important that any spills of antifreeze are cleaned up immediately and that containers are stored safely out of reach of your pet. Where possible use a less toxic antifreeze that does not contain ethylene glycol.

Symptoms Initially your dog may be wobbly and uncoordinated, vomiting, drooling. Your pet may appear to then recover before developing kidney failure a few days later and become depressed, in appetent, vomiting, have seizures and possible coma and death.


Chocolate contains theobromine which is toxic to dogs. While theobromine is not harmful to humans, dogs struggle to metabolise this substance. How much chocolate a dog can handle is individual and size dependent. Dark chocolate is much more dangerous than milk chocolate as it contains more theobromine. Cocoa powder is especially toxic. As well as theobromine chocolate also contains caffeine and large amount of sugar and fat which can also cause illness in your pet.

Contact your vet if you think that your pet has ingested chocolate. They will calculate if your pet has ingested a toxic amount of theobromine Your vet will want to know what type of chocolate has been consumed, how much chocolate has been eaten, approximate weight of your pet, how long ago the chocolate has been eaten and if your pet has any symptoms before deciding if your pet needs to be treated and how they are going to treat your pet.

It is important to keep chocolate and cocoa powder out of reach of your pet. This is particularly important at times like Easter, Christmas and Halloween when there can be more chocolate around the home.

Symptoms: It can take between 2- and 12-hours following ingestion for symptom to appear. Vomiting, abdominal pain, panting, increased thirst, restlessness and agitation, tremors, increased salivation, increased heart rate, high temperature, seizures. In very rare, severe cases chocolate poisoning can cause heart failure and death.

Grapes /Raisins

Ingestion of grapes/raisins/currants and sultanas can cause acute gastrointestinal issues and possible kidney failure in dogs. It does not matter if the grapes are seeded or seedless, white, green or red. The exact mechanism behind the toxic effect is not known, nor why some individuals are sensitive to grapes/raisins while others are not. No connection between the amount ingested and poisoning in dogs has been established. Your pet will need immediate urgent veterinary attention if it has consumed grapes, raisins, currants or sultanas, if left untreated your pet can develop kidney failure which could lead to death. If you bring your pet to the vet soon after consumption of raisins/grapes your vet will try to induce vomiting and possibly administer activated charcoal to try to prevent toxins being absorbed. Your pet will then require supportive therapy and monitoring. Care is needed at Christmas time and Easter time when there are more foods containing raisins, currants and sultanas in the home e.g., Christmas cake, mince pies, hot cross buns.

Symptoms:Vomiting, abdominal pain, lethargy, diarrhoea, reduced appetite. It may take a few days following ingestion for kidney failure to develop.


Onions contain allicin, which is toxic to dogs. Allicin is found in both raw and cooked onions and can cause anaemia in your dog. Garlic, chives and leeks are also toxic as they are also alliums. Alliums contains toxins that cause damage to red blood cells and can cause anaemia when consumed by dogs. It is difficult to know how much onion can lead to poisoning and it is thought that some dogs are more sensitive to onion poisoning than others. Therefore, do not give your dog any kind of onions. Important to consider for those of you who usually give your dog food scraps is that our food often contain large amounts of onions. If you think your pet may have eaten onions, garlic, chives or leeks please contact your vet for advice.

Symptoms: Diarrhoea, vomiting, abdominal pain, convulsions, decreased appetite, breathing problems, pale mucous membranes, lethargy and in rare cases seizures can occur.


Macadamia nuts are considered very toxic to dogs. Raw cashew nuts, black walnuts and old/mouldy walnuts are also unsafe for your pet. Please keep in mind that salted nuts can lead to salt poisoning in your dog. Nuts can also be a choking hazard and can potentially cause gastrointestinal obstruction. Nuts are also high in fat and are dense in calories.

Symptoms:( Macadamia Nut Toxicity) Depression, weakness, decreased appetite, vomiting, unsteadiness, tremors fever, abdominal pain.


If you dog consumes significant amount of salt it could develop hypernatremia (too much salt in the bloodstream). Salt dough and ornaments made from salt dough pose a hazard to your pet. Also take care in cold weather that your pet does not ingest rock salt used to grit roads. Dogs can also develop salt poisoning if it drinks salt water without enough access to fresh water. Urgent veterinary attention is required if you think that your pet is showing signs of salt toxicity.

Symptoms: Extreme thirst, vomiting, diarrhoea depression, muscle spasms, cramps, weakness incoordination, seizures and can lead to coma and death


Ingestion of unbaked bread dough can be dangerous if eaten by your dog. The dough will expand in the stomach, therefore bloat and abdominal distention can develop. There is also the risk that a life-threatening condition called gastric-dilation volvulus (GDV) can develop. Dogs can also develop alcohol toxicity as the dough ferments in the stomach. Alcohol toxicity can cause low blood sugar and low blood pressure and reduce body temperature.

Seek veterinary advice if you think your pet has consumed unbaked bread dough or is showing signs of bloat or alcohol toxicity as your pet’s life could be at risk. Be careful to put the dough out of reach of your dog.

Symptoms: Abdominal distention, unproductive retching, vomiting, lethargy, weakness, unsteadiness, staggering, seizures, respiratory failure, coma.


Xylitol is contained in toothpaste, mouthwash, chewing gum and in “sugar free” and low sugar products. It is very toxic for dogs even if consumed in small amounts. Xylitol causes low blood sugar in dogs and can also cause liver failure. Never give your pet anything containing xylitol. If you suspect your pet has eaten something containing xylitol, veterinary intervention will be required urgently. Xylitol toxicity can be fatal especially if there is any delay in getting your pet to the vet.

Symptoms: Vomiting, shaking, lethargy, disorientation, tremors, seizures, unconsciousness. Can lead to death.


Toads have glands under their skin that secrete a poison that dogs are sensitive to. Your dog can become poisoned by chewing or licking a toad. If your pet has had contact with a toad and is displaying symptoms, contact your vet as your pet may need supportive care.

Symptoms: Hypersalivation, retching, vomiting, head shaking, pawing at mouth.

Slug Bait

Slug and snail bait is very dangerous for our dogs. These pesticides contain metaldehyde which is toxic if ingested or inhaled by your pet. Your pet will likely become symptomatic very quickly after it has consumed the bait. Metaldehyde ingestion causes acute and severe symptoms and can be fatal in some cases. If you suspect that your dog has eaten or come into close contact with slug or snail bait or is showing any symptoms, you will need to contact your vet immediately. Keep the packaging of the bait and show it to your vet.

Symptoms: Increased salivation, nausea, vomiting, weakness, tremors, seizures, breathing difficulty, gums are blue-tinged, distress, incoordination, poor balance, fast heart rate, collapse, coma.


Acorns contain tannin, which is poisonous to dogs. If the dog ingests a high dose, it can cause kidney or liver failure. All parts of the oak tree are poisonous. Acorns are also a choking hazard or could cause gastrointestinal obstruction if ingested. Contact your vet if you think your pet has eaten acorns. Fortunately, acorns taste bitter, so dogs don’t usually like to eat them.

Symptoms: Vomiting, Lethargy, Abdominal Pain, decreased appetite, shaking, red itchy skin, bloody diarrhoea, kidney damage, liver damage.

Blue-green algae

Dogs that bathe or drink water from lakes or streams during algal blooms can suffer from poisoning. Blue-green algae contain algal toxins (cyanobacteria) that are toxic to your dog. Whether or not your dog becomes poisoned depends on the levels of algae toxins in the water, how long your dog bathes and whether the dog drank from the water.

If your dog has swam in water containing algae, rinse and shampoo the dog immediately. Make sure your dog doesn’t lick his fur. Contact your vet urgently if you think your dog has been exposed to blue-green algae. It is best to avoid walking your dog near water with obvious accumulation of algae. It is also advisable to feed and water your dog before walking to reduce the need for your pet to drink from ponds, lakes and rivers.

Symptoms: Diarrhoea, vomiting, drooling, fatigue, weakness, breathing difficulties, disorientation, seizures. Can cause organ failure and death.

Wild Mushrooms and Fungi

Your pet may encounter poisonous wild mushrooms and other fungi when out on walks especially in woodland areas. Consumption of some types of fungi can make your pet very ill, other types can even be fatal if ingested. If you suspect that your dog has eaten poisonous mushrooms, it is important to contact a veterinarian as soon as possible.

Symptoms: Vomiting, diarrhoea, lethargy, jaundice, drooling, incoordination, tremors, seizures, collapse.


There are an infinite number of types of plants, and it can be difficult to know which ones are dangerous for your dog and which are not. If you are unsure whether a plant is poisonous or not, you can contact your veterinarian.