Common Poisons
If you think that your pet may have eaten, touched or inhaled something that it shouldn’t have, consult us, your local veterinary practice immediately.
In emergencies you can help us to make an informed decision as to whether your pet needs to be treated and if so, what the best treatment would be.
Where possible, you should gather information on:
What poison you think your pet has been exposed to such as ibuprofen, chocolate, etc. Include any product names or lists of ingredients.
How much they may have been exposed to, for example 500mg, 500ml, one tablet etc, even approximations may help)
When your pet was exposed to the poison (i.e. 5 minutes, 5 hours or 5 days ago)
If your pet has been unwell, and if so, what clinical effects have been seen It is easier for a veterinarian to care for a poisoned pet if they are treated sooner rather than later.
If you are in any doubt, do not wait for your pet to become unwell before calling for advice.
If you do need to bring your pet to one of our practices, make sure that you take along any relevant packaging, or a sample of the poison, i.e. parts of plant or fungi. Always make sure that you yourself are protected and can not be poisoned in turn.

Alcohol
Ethanol poisoning occurs from exposure to the chemical ethanol, either orally or through the skin and results most commonly in a depression of the central nervous system, expressed in the animal as drowsiness, lack of coordination or unconsciousness.
Other effects may include damage to body cells and symptoms such as incontinence, slowed heart rate, seizure or collapse. Ethanol poisoning can occur from ingesting a variety of products such as fermented products, e.g. bread dough and rotten apples.
Other accidental instances may occur from spilled beverages, commercial products or medications containing alcohol.
Exposure of alcohol-containing products through the skin is also possible.
Some cases of intentional ethanol poisoning have been reported as dogs may readily consume alcoholic beverages if offered by an owner unaware of the consequences.
Clinical signs to look out for:
Hyperactivity
Restlessness
Vomiting
Increased heart rate
Abnormal heart rhythms
Hyperthermia (increased body temperature)
Seizures
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Antifreeze
Ethylene glycol (antifreeze) ingestion is extremely dangerous. It is sweet-tasting which pets can sometimes be drawn towards ingesting. Even a relatively small quantity such as a teaspoon can cause serious kidney damage and can be fatal to both dogs and cats.
Unfortunately the longer the delay between ingestion of the antifreeze and initiation of treatment, the less favourable the prognosis.
Sources of ethylene glycol include automotive antifreeze (radiator coolant, which typically contains 95% ethylene glycol), windshield de-icing agents, motor oils, hydraulic brake fluid, developing solutions for photography, paints, solvents, etc.
Clinical signs to look out for:
Drunkenness
Excessive thirst or urination
Vomiting
Panting
Lethargy
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Blue-Green Algae
Blue-green algae can be found in many types of waterbody throughout the UK (i.e. ponds, streams, lakes, estuaries etc.) and these can produce toxins which may be harmful to animals and humans.
The types of chemicals produced by the algae may vary and can therefore cause a wide range of different clinical effects. These effects can range from vomiting and diarrhoea (both of which may be bloody) to lethargy, effects on the heart and blood pressure, twitching, problems breathing, liver and kidney impairment or can even cause death shortly after exposure.
Dogs are most commonly exposed when swimming, playing in or drinking from contaminated water.
Water that contains blue-green algae may appear a different colour, or may be recognisable from coloured algal blooms, appearing on the surface of the water, or close to the shore. Unfortunately, it is impossible to know if there are any toxins present in the water without testing.
The amount of algae in a body of water may vary throughout the year, but is likely to be at its greatest in, or after, hot and sunny periods (i.e. mid to late summer) and will vary depending on the amount of nutrients available in the water.
If you come across a body of water that is known to contain blue-green algae, do not let your dog swim in it or drink from it.
Clinical signs to look out for:
Vomiting (can contain blood)
Diarrhoea (can contain blood)
Lethargy
Seizures
Caffeine
Humans continue to drink and use more and more caffeine, making pets more frequently exposed to this dangerous chemical.
There are several sources of caffeine in the house: in coffee, coffee grounds, tea, soda, energy drinks, weightlifter supplements and diet pills.
Dogs and cats appear to be more sensitive to the effects of caffeine than people. While 1-2 laps of coffee, tea or soda will not contain enough caffeine to cause poisoning in most pets, the ingestion of moderate amounts of coffee grounds, tea bags or 1-2 diet pills can easily cause death in small dogs or cats.
When ingested, clinical signs of hyperactivity, restlessness, vomiting, an elevated heart rate, hypertension (elevated blood pressure), abnormal heart rhythms, tremors, hyperthermia (elevated body temperature), seizures, collapse and death may be seen.
Clinical signs to look out for:
Hyperactivity
Restlessness
Vomiting
Increased heart rate
Abnormal heart rhythms
Hyperthermia (increased body temperature)
Seizures
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Chocolate
Chocolate contains a toxic chemical called theobromine. The darker the chocolate the more theobromine it contains, therefore white chocolate contains relatively little and so may only cause an upset stomach whereas even a small portion of dark chocolate or cocoa powder can cause severe theobromine poisoning resulting in issues such as pancreatitis or life threatening problems with the heart if not treated promptly.
Although not poisonous, wrappers from chocolate can cause obstructions if ingested and may need surgical intervention, so again it is best to seek veterinary advice and treatment promptly.
Signs of an obstruction may include vomiting, lethargy and your dog being off their food, not defecating or struggling to defecate.
Clinical signs to look out for:
Vomiting
Diarrhoea
Excitability / Hyperactivity
Lethargy
Off food
Seizures
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Flowers & Plants
Incidents of poisoning from spring bulbs are most likely to occur from dogs eating the bulbs in autumn when they are planted, or in spring when they begin to flower.
Daffodils
Effects from poisoning can include vomiting, stomach upset and salivation, but can escalate to dogs appearing lethargic, wobbly on their legs, or collapsing. In more serious cases, seizures and changes to heart rate, body temperature and blood pressure can occur. Dogs can also become unwell if the flowers are eaten, or if water from a vase containing daffodils is drunk.
Tulips
The toxins found in this plant cause irritation to the mouth and gastrointestinal tract and usually only result in drooling, vomiting and diarrhoea. Serious cases are rare, but effects could include heart problems and breathing difficulties.
Spring crocus
These flower in spring and are said to be of low toxicity and may only cause a mild stomach upset if eaten. These bulbs are not to be confused with autumn crocus, which flower in autumn and can cause severe stomach upset, kidney and liver problems and bone marrow depression.
Clinical signs to look out for:
Vomiting
Stomach upset
Excessive salivation
Lethargy
Seizures
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Grapes, Currants & Raisins
Grapes, raisins, currants and sultanas are all toxic to dogs and it is believed the dried forms of these fruits are even more toxic. It is not known exactly why these fruits are poisonous to dogs, or how much is dangerous.
Some dogs have eaten large quantities of these fruits and had no effects, whilst others have become extremely unwell after very small amounts.
As well as causing stomach issues, these fruits can cause kidney failure, which can sometimes be delayed by up to three days. Kidney failure may sometimes present as a decrease in urination or your dog may also appear lethargic and weak and show signs of increased thirst.
Prompt treatment is very important. If your dog does eat any amount, contact us immediately so treatment can become promptly.
It is important not to let dogs eat any foods that contain these fruits, such as hot cross buns, Christmas cake, Christmas pudding, fruit cake, mince pies etc.
Clinical signs to look out for:
Lethargy
Increased thirst
Decrease in urination
Vomiting
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Human Medication
Anti-histamines
From spring to early summer the pollen count is at its highest and this is when owners are likely to be stocking up on their anti-histamine medication. Ingestion of large amounts of anti-histamines result in signs that may include vomiting, lethargy, incoordination, wobbliness and seizures. Signs develop within 4-7 hours of ingestion. Some dogs may become hyperactive and hyper-excitable and if large amounts of anti-histamine have been eaten convulsions, respiratory depression and a coma may occur.
Ibuprofen and Other Non-Steroidal Anti-inflammatory Drugs (NSAIDs)
NSAIDs are often used to manage inflammation and pain in both humans and dogs. Human NSAIDs, such as ibuprofen, diclofenac and naproxen are different from the ones given to dogs and cats and can make them very unwell. Human NSAIDs (and dog NSAIDs in overdose) interfere with the dog’s ability to protect its digestive system and therefore can cause severe stomach upset. Ulcers may form in the gut, leading to blood in the stools and vomit. Kidney failure can also occur and may be delayed for several days. Signs of kidney failure may include inappropriate urination and increased thirst. Some NSAIDs can also cause seizures.
Oral Contraceptives
These small tablets are one of the medications most frequently eaten by dogs. Fortunately, oral contraceptives are of low acute toxicity and even large amounts are unlikely to cause any major concerns, apart from a possible mild stomach upset. Some oral contraceptives may temporarily disrupt oestrus in bitches.
Paracetamol
This widely used pain medication may initially cause vomiting, brown coloured gums, increased heart rate, changes to the rate of breathing, swelling to the face and paws and can also cause delayed liver failure, that may not present for several days. Paracetamol can also be found in many other over the counter medications in combination with other drugs.
Clinical signs to look out for:
Vomiting
Diarrhoea
Blood in faeces
Blood in vomit
Increased thirst
Increase in urination
Seizures
Upset stomach
Increased heart rate
Changes in respiratory rate
Mushroom & Fungi
There are thousands of different fungi in the UK, varying dramatically in shape, size, colour and how poisonous they are.
Although some fungi may be fairly distinct in appearance, it is incredibly difficult to identify most wild mushrooms. Some fungi are edible, while others are extremely dangerous and sadly it is not always easy to tell the difference between the two.
Signs of poisoning may vary dramatically depending on the type of fungi eaten and may include stomach upset, blood in the stools or vomit, neurological effects such as hallucinations or seizures, kidney or liver failure.
The type of fungi eaten will determine the onset of effects, which can be very sudden, i.e. ten minutes after eating the fungi, or may be delayed by days, or even in some rare instances by several weeks.
If your dog does eat an unknown wild mushroom, take them to the vets immediately and if possible, bring along a picture, or ideally a sample of the fungi.
Take note of the area where the fungi was found (i.e. was it growing in grass or on a tree stump etc.) as this may help identify what fungi your dog has eaten should they become ill.
Clinical signs to look out for:
Upset stomach
Vomiting
Diarrhoea
Neurological effects
Seizures
Onions & Garlic
Onions, garlic, leeks, shallots and chives all belong to the Allium species.
These plants all contain a toxic substance called thiosulphate which can damage red blood cells in dogs and cats and can cause life threatening anaemia.
Signs may not present for a few days but can include digestive issues and may cause your pet to become lethargic, dull, weak or develop rapid breathing. Poisoned dogs may also have discoloured urine.
Ensure that your pet does not eat cooked foods that contain these vegetables such as onion gravy, onion bhaji, vegetable soups etc.
Clinical signs to look out for:
Lethargic
Weak
Increased respiratory rate
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Slug/Snail Pellets and Rat Poison
Metaldehyde based pellets are among the most dangerous and common poisonings seen in dogs.
Even small amounts of pellets can cause significant poisoning and severe signs can occur within an hour of consumption.
Dogs that have eaten pellets need to be seen immediately as rapid intervention can save their life.
Intensive treatment involving heavy sedation, control of convulsions and associated life support measures is often needed.
Clinical signs to look out for:
Incoordination
Muscle Spasms
Muscle rigidity
Seizures
Xylitol
Some sugar-free sweets, sugar replacements (sweeteners), chewing gums, nicotine replacement gums and even some medicines contain an artificial sweetener called xylitol, which can be very poisonous to dogs and cats.
Xylitol can cause an otherwise healthy dog’s blood sugar level to quickly drop to dangerous levels and larger amounts can also cause liver failure.
It is important to read ingredient lists of food products before offering to your pet such as certain peanut butter products.
Clinical signs to look out for:
Lethargic
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Seizures