Cats are most commonly exposed to poisons by eating them, but they can also be inhaled or absorbed through the skin. Most poisons do not have an antidote and vets will usually treat the signs of poisoning until it’s safely removed from the cat’s system.

If you notice a change in your cat’s health, such as vomiting, diarrhoea, incoordination or changes in appetite or thirst, it may be down to poisoning. Other signs that your cat has been poisoned include foreign material on his hair or feet or a strange smell to his hair, breath, sick or faeces.

Spring and summer

Permethrin (insecticides). Permethrin is an insecticide commonly found in over the counter ‘spot-on’ flea treatments for dogs. It’s very toxic to cats and unfortunately at Vets Now we see numerous cases every month. Poisonings happen all year round, but there is a peak in late summer as this is when flea numbers are at their highest. Cats are most commonly poisoned after their owners mistakenly use a dog product on the cat, but they can also show mild signs after close contact with a recently-treated dog.

The effects of insecticide poisoning are usually rapid in onset. Signs include drooling, tremors, twitching and seizures. Any remaining product should be washed from your cat’s hair coat (or clipped in long haired cats) using cool water, as warm water will increase absorption of the product. Controlling the convulsions is often difficult, and your cat may need to be hospitalised for several days. The Veterinary Poisons Information Service reports that 15% of cases of insecticide poisoning result in death or euthanasia. However, cats who receive immediate treatment typically survive and usually suffer no long-term effects.

Toad toxicity. We see sporadic cases of exposure to toads in the summer months when the toads are spawning. Toads are most active at dawn and dusk, and most toad-related incidents occur in the evening when cats lick them. The onset of signs of poisoning is rapid, and you can see drooling, frothing, foaming, pain around the mouth, vomiting, wobbliness, seizures and collapse in severe cases.

Slug and snail pellets (Metaldehyde). This is a common poison we see in dogs. However, we also see occasional cases in cats. The toxic compound is metaldehyde, although it’s worth noting not all slug pellets contain metaldehyde. Only small amounts of pellets are needed to cause significant poisoning. Signs will be seen within an hour of ingestion and include incoordination, muscle spasms, twitching, tremors and seizures. Pets need urgent veterinary treatment if they are to survive poisoning with slug pellets.

Anti-histamines. Antihistamines are quite low toxicity – your cat needs to eat quite a few to cause problems. However, ingestion of large amounts of anti-histamines can result in signs including vomiting, lethargy, incoordination, wobbliness and tremors. Signs can be seen within four to seven hours of ingestion. Some cats can become hyperactive and hyper-excitable.

Autumn and winter

Ethylene Glycol. Unfortunately, ethylene glycol poisoning is commonly seen in cats. Ethylene glycol is the compound in most types of antifreeze and is also present in other products. It smells and tastes sweet, so cats will drink it from puddles and spills on the ground. They might also lick it off their paws if they walk through it. The toxic dose is very small and even a few drops of ethylene glycol in a puddle will be enough to cause severe kidney damage and can be fatal. Signs will be seen within the first few hours after ingestion but are mild and easy to miss.

Luminous necklaces. These consist of plastic tubing with a core of luminescent chemicals, which are apparently attractive to cats. The chemical mixture is irritating to the mouth – commonly causing drooling, foaming at the mouth, vomiting and stomach pain. While these signs look dramatic, ingestion is unlikely to cause significant problems, with effects mostly limited to gut and mouth. Contact your vet for further advice.

Human medications

Assume all human medications are poisonous to your cat unless instructed otherwise by your vet. Some over-the-counter pills such as paracetamol are highly toxic to cats and can lead to kidney or liver failure and even death.


Animal medications

Increasingly animal medications are being made ‘palatable’ to make them easier to give to your pet. The downside is that if your cat gets hold of the drugs, they may eat more than they should. Make sure you keep all animal medications safely locked away to prevent your pet from self-overdosing.


Inhaled Toxins

A variety of inhaled substances can have adverse effects on cats. In general, these substances are the same things that would cause problems for people such as carbon monoxide, smoke, fumes from bleach and other cleaning products and sprayed insecticides. Most of these substances irritate the airways. If your cat is exposed to an inhaled toxin, move him immediately to an open, well-ventilated area with clean air, then call your veterinary surgeon for further advice.


Contact Dermatitis

Contact dermatitis can occur if your cat comes into contact with something that causes irritation to the skin. If your cat licks or swallows these toxins, his mouth and digestive tract can be affected as well. Look out for any foreign substance on your cat’s body and feet, any unusual smells, especially a chemical smell, redness, swelling, hair loss, itchiness, blisters, or ulcers on the skin or feet where the substance is located. You may see drooling, coughing, sores in the mouth, vomiting or diarrhoea, if your cat swallowed the substance. Contact dermatitis is most commonly caused but household chemicals, insecticides, and petroleum products.

How to prevent poisonings

Keep all chemicals, medications, plants and food items out of cat’s reach. Ensure you read all labels carefully and follow product guidelines on species, age and weight. Also wear protective gloves when handling potentially poisonous substances around your pet.

If you suspect your cat has been poisoned, try to identify the poison involved and bring the container label, plant or any other information you have with you when you visit the vet.