Common Types of Poisoning in Pets
Below is an overview of common poisonings in pets and their associated symptoms.
Chocolate
Chocolate is toxic to pets. This type of poisoning is most commonly seen in dogs, as they sometimes have a tendency to eat food left on tables and do not hesitate to consume chocolate, packaging included. The toxic substance in chocolate is theobromine. The amount of theobromine varies depending on the type of chocolate. In general, the darker the chocolate, the higher the theobromine content. Sensitivity to chocolate poisoning differs between animals. This means that one animal may show signs of poisoning after consuming a certain amount of chocolate, while another animal may show no symptoms at all after consuming the same amount. As an example, a 5 kg dog may develop mild poisoning symptoms after eating 16 grams of dark chocolate or 50 grams of milk chocolate. Symptoms can appear within an hour, although in some cases they may not occur until 24 hours later.
Symptoms generally include vomiting, diarrhoea, hyperactivity, muscle tremors, seizures and heart rhythm disturbances. In severe cases, poisoning can be fatal.
Read more in our article What If My Dog or Cat Eats Chocolate?.
In addition to theobromine, caffeine and all other substances from the methylxanthine family are potentially dangerous to pets.
Grapes, Currants and Raisins
We do not know exactly which substance in grapes is toxic. Sensitivity varies from dog to dog, just as with chocolate. However, for small dogs, as few as two grapes may be fatal. Symptoms can develop within 6 to 24 hours.
Symptoms include vomiting, diarrhoea, abdominal pain, increased drinking, weakness and loss of appetite. Ultimately, kidney failure may occur. The toxicity applies to fresh grapes as well as raisins and currants.
Avocado
Avocado is toxic from approximately 60 mg per kg of body weight. After eating avocado, dogs and cats mainly develop gastrointestinal symptoms such as abdominal pain and vomiting. Due to the high fat content of avocado, this can in some cases lead to pancreatitis. In addition, the large stone can cause an intestinal blockage.
Rodents, rabbits and birds are even more sensitive to avocado. If a bird eats avocado, it may die within 24 to 48 hours. The first symptoms include poor feather condition, lethargy, loss of appetite and breathing difficulties. In rabbits, avocado may cause heart problems. Avocado is also toxic to horses and may cause colic and fluid accumulation around the abdomen, head and neck.
Onion Family Plants
Onions, shallots, garlic, chives and leeks. All plants from the Allium family are toxic to animals. The toxic substances in these plants are organosulphides. These affect red blood cells and can cause anaemia due to red blood cell destruction. This may result in pale or yellow mucous membranes, lethargy, weakness, a rapid heart rate and rapid breathing. Ingestion may also lead to vomiting, diarrhoea, abdominal pain and reduced appetite.
Symptoms can develop very quickly, regardless of whether the product is dried, processed or raw. It also makes no difference whether your pet eats it once or repeatedly.
Garlic is a commonly used ingredient in natural flea and tick products, such as Biofood Garlic Tablets for dogs and cats.
Macadamia Nuts
Macadamia nuts contain a substance that can affect the nervous system of animals. The exact substance is unknown. Symptoms generally occur between 3 and 24 hours after ingestion.
Possible symptoms include muscle weakness or tremors, stiffness and joint pain, vomiting or abdominal pain, pale mucous membranes and overheating.
In most cases, recovery occurs within 24 hours.
In addition to their toxic properties, macadamia nuts may also cause intestinal blockages, particularly in smaller animals.
Xylitol
Xylitol is a sugar substitute used in chewing gum and sweets. It is also found in some low-sugar products. Xylitol can cause hypoglycaemia (low blood sugar), resulting in symptoms such as vomiting, weakness and other neurological signs. Eventually, liver damage may occur, with associated symptoms including vomiting, jaundice, diarrhoea, clotting disorders and neurological problems.
Alcohol
Animals are more sensitive to alcohol than humans. Ingestion of alcohol can lead to liver failure and may ultimately result in coma or death. Symptoms that may occur include lethargy, difficulty walking, loss of consciousness, hypothermia, vomiting and diarrhoea.
Paracetamol
Paracetamol is regularly given to pets due to a lack of awareness. However, caution is advised: paracetamol is toxic. This is particularly true for cats, but also for dogs. Cats can die following the administration of paracetamol. It causes liver and kidney damage, severe anaemia with dark mucous membranes and red urine. An antidote is available, namely acetylcysteine, to counteract the effects of paracetamol. Therefore, always contact your veterinarian as quickly as possible.
Ivermectin
Ivermectin is a substance used as an active ingredient in some worming treatments for livestock. Dogs can ingest this substance when they eat horse manure from horses that have recently been wormed. It is also used in ear ointments for treating ear mites in cats.
However, this active ingredient can be toxic to Collie-type dogs and several other dog breeds, including Border Collies, Rough Collies, Bearded Collies, Shetland Sheepdogs, Australian Shepherds, Australian Cattle Dogs, Old English Sheepdogs, German Shepherds, White Swiss Shepherds, Long-haired Whippets, Silken Windhounds and crosses involving Collie-type breeds.
Due to a mutation in a specific gene, these breeds may lack a protein that helps protect the brain from certain medications. Without this protein, the substance can accumulate in the brain. This can lead to neurological symptoms such as blindness, heightened startle responses, disorientation, weakness and coma.
Permethrin
Permethrin (or a similar active ingredient, deltamethrin) is used in flea and tick treatments for dogs, such as Advantix Spot-On (not to be confused with Advantage), Pulvex Spot-On, the Scalibor Collar and Defencare Shampoo.
These products must never be used on cats, as permethrin is highly toxic to them. Symptoms include vomiting, excessive salivation, tremors and epileptic seizures. As a result, the cat may die.
If you have accidentally administered one of the above products to a cat, contact your veterinarian immediately. It is also essential to wash the cat as soon as possible with soap to remove the active ingredient from the coat and limit further absorption.
Christmas Plants
Mistletoe and holly are often used as Christmas decorations. However, the berries of these plants are toxic to pets. Poinsettias and Christmas roses may also cause health problems. Below is a brief overview:
- Poinsettia (Euphorbia pulcherrima) may cause temporary gastrointestinal symptoms such as vomiting, loss of appetite and lethargy.
- Holly (Ilex aquifolium) may cause gastrointestinal symptoms such as drooling, vomiting, diarrhoea and loss of appetite when large quantities are consumed. In general, these symptoms are temporary.
- Mistletoe (Viscum album) can cause serious health problems. In addition to gastrointestinal symptoms, it may also cause shock and death. Therefore, make sure that pets have absolutely no access to it.
- Christmas rose (Helleborus niger) is also quite toxic. It contains natural cardiac glycosides that make the heart beat more forcefully. Ingestion can cause gastrointestinal symptoms similar to the other plants, but may also result in drowsiness, paralysis and heart rhythm disturbances.
Also be careful with Christmas tree needles; some tree species are toxic to certain animal species.
Lily
Lilies are popular houseplants, and not all pet owners are aware that lilies are highly toxic to cats. It is believed that all parts of the plant (stem, leaves and flowers) are toxic to cats. Eating even a small piece of the plant can cause signs of poisoning.
The first symptoms are vomiting, drooling and lethargy. These generally occur 1 to 3 hours after ingestion. Eating this plant can cause acute kidney failure within 12 to 30 hours, and the prognosis is poor. There is no known antidote.
Take a look at our blogs Which Plants Are Poisonous to Your Cat?.
Acorns
Many people are unaware that acorns and oak leaves contain tannins. If a dog consumes a large amount, this can be toxic. The animal may develop abdominal pain, diarrhoea and vomiting. Eventually, it can lead to kidney failure and death.
Acorns can also cause intestinal blockages or damage to the intestines. Read more in the article Acorns Are Toxic to Dogs. Take Care During Autumn Walks!.
Rat Poison
Rat poison contains coumarin derivatives that are toxic to rats and mice, but also to dogs and cats. Therefore, always ensure that these products are kept out of reach of pets.
These substances have a long-lasting effect on blood clotting and can cause internal bleeding, which may prove fatal. The dosage at which these problems occur varies between products.
Always contact your veterinarian and take the packaging of the rat poison involved with you. Treatment consists of administering vitamin K for an extended period, ranging from several weeks to several months, as it plays an important role in blood clotting.
Antifreeze
Antifreeze contains ethylene glycol and is toxic to both dogs and cats. Antifreeze can be particularly attractive to dogs because it has a sweet taste. Therefore, always store this product safely in a location that dogs cannot access.
The initial symptoms of poisoning include vomiting, increased drinking and urination, lethargy and an unsteady, drunken gait. This is followed by kidney failure, which is often fatal.
Drugs
Dogs can become poisoned by drugs after eating the faeces or vomit of drug users. Unfortunately, this occurs with some regularity. The symptoms are similar to those seen in humans under the influence of drugs.
The animal may show weakness, collapse on its legs, display an unsteady gait and appear disoriented, lethargic and easily startled.
Species-Specific Poisoning Risks
Take care with raw eggs and raw freshwater fish when feeding dogs and cats. In their raw state, these contain enzymes that destroy B vitamins in a cat’s body. Consuming large quantities can cause health problems.
Birds are highly sensitive to PTFE, which is released when Teflon is heated. Read our blog “Cooking at the Table and the Danger to Birds” for more information.
If in doubt, always contact your veterinarian as soon as possible. The earlier a poisoned animal receives treatment, the better the prognosis is often likely to be.
