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What to do if you think your pet has been poisoned

What is out there that your pet should not indulge in?

Sadly and worryingly there are many substances that are poisonous to our pets. Firstly, should you ever be worried, concerned or unsure, please do not hesitate to contact us. Should this happen at night or times when you think the main clinic is closed, remember we have our 24 hour emergency cover should you need advice or your pet needs treatment. Click here for our emergency contact information.

There are lots of different chemicals, drugs and plants that are poisonous to our pets. Here is an overview of common poisons.

Symptoms of poisoning

  • Contact poisons – chemicals or plants that come into contact with your pet’s skin can cause irritation. You may see sign of discomfort, agitation, excessive scratching, swellings (hives) or pain.
  • Swallowed poisons – can cause gastrointestinal irritation, vomiting, diarrhoea, restlessness, staggering, disorientation, convulsions, lethargy, loss of appetite, twitching, dilated pupils, ulcers, heart palpitations, and coma.
  • Inhaled poisons – coughing, drooling, difficulty breathing, unconsciousness or coma

Poisons for which immediate care should be sought

Skin contact

  • Tar
  • Petroleum products
  • Household chemicals
  • Paint or paint remover
  • Gasoline
  • Stinging nettles
  • Flea and tick medication – if overdosed, or if dog products are used on cats

Inhaled poisons

  • Smoke
  • Tear gas
  • Insecticides
  • Household chemicals
  • Swallowed poisons


  • Acids
  • Household and garden chemicals
  • Petroleum Products
  • Antifreeze, screen wash
  • All drugs/medications – human or pet
  • Luminous necklaces/glow sticks
  • Batteries

Poisonous plants

  • Ivy
  • Foxglove
  • Hemlock
  • Mushrooms
  • Mistletoe
  • Oleander
  • Lilies, including daffodils
  • Tulip
  • Oak/acorns

Food items

  • Chocolate
  • Onions, garlic, chives
  • Raisins/grapes
  • Caffeine
  • Alcohol
  • Avocados
  • Macadamia nuts
  • Xylitol (an artificial sweetener commonly used in chewing gum and diabetic sweets)

What to do if you think your pet has been poisoned - immediate care

Contact your vet immediately upon ingestion or exposure to any known or possible toxin with as much information as possible regarding the toxin (name, strength, amount ingested).

  • If the poisoning is primarily from noxious fumes or a gas, get your pet to fresh air, but don’t put yourself at risk for poisoning.
  • If the poisoning is by contact with the skin, wear protective gloves and remove the substance from the skin/hair. Use paper towels or clean rags to remove liquids. Do not use water, solvents or anything else to remove the poison unless specifically directed to do so by your vet.
  • If the poison was in the mouth or swallowed, contact your vet. DO NOT induce vomiting unless specifically directed to do so, as some poisons can cause more damage if vomiting occurs than if left in the stomach.


What to be aware of? These are some things in particular that will cause a problem in dogs.


Chocolate contains a stimulant called theobromine (a bit like caffeine) that is poisonous to dogs. The amount of theobromine differs between different types of chocolate (dark chocolate contains the most). Theobromine mainly affects the heart, central nervous system and kidneys. Signs of theobromine poisoning will occur from 4-24hours following ingestion and will vary depending on the amount of chocolate (theobromine) your dog has eaten. You may see vomiting, diarrhoea, restlessness, hyperactivity and seizures.
There is no antidote to theobromine. In most cases your vet will make your dog vomit. Other treatments will depend on the signs your dog is showing. They may need intravenous fluids (a drip) and medication to control  their heart rate, blood pressure and seizure activity (fits).


Caffeine is found in the fruit of the plant that is used to make coffee. Like chocolate it contains stimulants.
Dogs are more sensitive to the effects of caffeine than people. A couple of laps of tea or coffee will not do any harm, but the ingestion of moderate amounts of coffee grounds or tea bags can lead to serious problems. Signs are similar to chocolate toxicity and treatment is broadly similar.

Onions, Garlic, Chives

These vegetables and herbs can cause gastrointestinal (stomach and gut) irritation and could lead to red blood cell damage. Although cats are more susceptible, dogs are also at risk if a large enough amount is consumed.
Onions are particularly toxic and signs of poisoning occur a few days after your dog has eaten the onion. All forms of onion and relatives of the plant can be a problem including spring onions, leeks, dehydrated onions, raw onions, cooked onions and table scraps containing cooked onions and/or garlic. Left over pizza, chinese food and commercial baby food containing onion can cause illness.


Alcohol is significantly more toxic to dogs than to humans. When consumed, alcoholic beverages and alcoholic food products may cause vomiting, diarrhoea, decreased coordination, central nervous system depression, difficulty breathing, tremors, abnormal blood acidity, coma and even death. So, remember to keep alcoholic beverages well out of the reach of your dog!


A substance called Persin that is contained in the leaves, fruit, seeds and bark of avocados can cause vomiting and diarrhoea in dogs. In addition birds and rodents are particularly sensitive and serious reactions such as the development of congestion, difficulty breathing and fluid accumulation around the heart can result.

Grapes & Raisins

The toxic substance that is contained within grapes and raisins is unknown; however these fruits can cause kidney failure. Dogs that already have certain health problems may have an even more serious reaction so this is certainly one to avoid.

Macadamia Nuts

Within 12 hours of ingestion macadamia nuts can cause dogs to experience weakness, depression, tremors, vomiting and hyperthermia (increased body temperature). These symptoms tend to last for approximately 12 to 48 hours, and as with all the other food groups mentioned if you suspect your dog has consumed macadamia nuts note the possible quantity consumed and contact your vet.

Yeast Dough

Ingestion of yeast dough can cause gas to accumulate in your dog’s digestive system as a result of the dough rising. Not only can this be painful but if may also cause the stomach or intestines to become obstructed (blocked) or distended. So whilst small bits of bread can be given as a treat because the risks are diminished once the yeast has fully risen, it is advised to avoid giving your dog yeast dough.


Whilst feeding your dog bones may seem like a good idea, it is important to remember that domestic dogs may choke on them, or sustain injuries as the bones can break dogs' teeth, and the splinters can become lodged in or puncture your dog’s digestive tract.  If you choose to give your dog bones be sure to keep an eye on then while they tuck in, avoid giving cooked bones because they splinter easily, or giving bones that are small enough to get stuck in their bowels.

Eating large quantities of bone can often cause constipation, so try to monitor the amount your dog manages to consume.

Corn on the cob

Corn on the cob may seem like a healthy table scrap to give your dog, but unlike most vegetables, it does not digest well in a dog’s stomach. If your dog swallows large chunks of the cob, or even whole, it can cause an intestinal blockage due to it’s size and shape. If your dog gobbled up corn on the cob watch for signs of trouble such as vomiting, loss of or reduced appetite, absence of faeces, or diarrhoea and signs of abdominal discomfort. In this case, contact your vet immediately.


The artificial sweetener xylitol is found in many foods such as sugar free gum, diabetic cakes, diet foods etc. It causes insulin release in many species leading to potentially fatal hypoglycaemia (lowered blood sugar levels). The initial symptoms include lethargy, vomiting and loss of coordination, followed by recumbency (inability to stand) and seizures. Xylitol has also been linked to fatal acute liver disease and blood clotting disorders in dogs. Even very small amounts can be extremely dangerous; if you think your dog has eaten any amount of xylitol you should seek veterinary advice immediately.


As dogs do not have significant amounts of the enzyme lactase that breaks down lactose in milk, feeding your dog milk and other milk-based products can cause diarrhoea or other digestive upset.

If you suspect that your dog has ingested any of these items, please note the amount ingested and contact your vet as soon as possible.

Poisons throughout the year – when are the risky times for dogs?

Spring and Easter poisons

Chocolate. Chocolate contains a stimulant called theobromine (a bit like caffeine) that is poisonous to dogs. The amount of theobromine differs in the different types of chocolate (dark chocolate has the most in it).
Raisins. Don’t forget that goodies such as hot-cross buns contain raisins. Grapes, raisins, currants and sultanas can cause renal (kidney) failure in dogs.

Spring flowers. Daffodils can be toxic, most often after ingestion of the bulb but occasionally after ingestion of flower heads and can cause vomiting, diarrhoea and lethargy that in severe cases may result in dehydration, tremors and convulsions. These signs can be seen from 15 minutes to one day following ingestion. Other spring flowers, such as Crocuses and Tulips, are considered to be less toxic but seek veterinary advice if you are worried your pet has ingested them.

Ivy. Dogs that eat ivy (Hedera helix) commonly develop salivation (dribbling), vomiting or diarrhoea. In more severe cases you may see blood in the vomitus or bloody faeces. Contact with ivy can cause skin reactions, conjunctivitis, itchiness, and skin rashes. Note that “Poison Ivy” is a different plant – Rhus radicans.
Bluebells. All parts of the plant are poisonous to dogs. Signs are related to stomach, intestine and heart function and include vomiting, diarrhoea and abdominal discomfort. There is a risk of heart beat irregularity (arrhythmia) if a significant quantity be ingested.

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 results in signs that may include vomiting, lethargy, incoordination, wobbliness and tremors. 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 coma may occur.

Summer poisons

Xylitol. Xylitol is an artificial sweetener commonly found in sugar free chewing gum, nicotine replacement gum, sweets and as a sugar substitute in baking. If ingested by dogs it causes hypoglycaemia (low blood sugar level). You may see vomiting, an increased heart rate, wobbliness, convulsions or coma. In severe case of hypoglycaemia fitting may result which if prolonged, can lead to permanent neurological (brain/nerve) damage. Liver failure has also been associated with the ingestion of xylitol in dogs. The onset of signs is often less than an hour but can be delayed for 24-48 hours after ingestion. Liver damage may also develop without the signs associated with hypoglycaemia and may occur up to 3 days after ingestion.

Ant powders, baits and gels. Ingestion of ant powders, baits or gels rarely results in significant poisoning. The active components of home use products tend to be at a low concentration and are often housed in containers e.g. ant bait stations. However ingestion of some products causes significant problems and you should contact your vet for advice. Signs you may see include constricted pupils, salivation, wobbliness, tremors and an increased body temperature. Severe cases may produce respiratory depression (not breathing fast enough), convulsions and coma and the duration of effects can be very prolonged.

Slug and snail pellets. Metaldehyde based slug pellets are among the most dangerous and common poisonings we see 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 slug pellets need to be seen ASAP as rapid intervention can save their life. Signs of poisoning can include; incoordination, muscle spasms, muscle rigidity, twitching, tremors and convulsions. Intensive treatment involving heavy sedation, control of convulsions and associated life support measures is often needed.

Toad toxicity. There are two species of toad native to Britain, the Common toad and the Natterjack toad. The Common toad is widespread, whilst the Natterjack toad is a protected species found in East Anglia and the North West of England. Exposure to toads occurs between June and August when they are spawning, toads being most active around dawn and dusk. Most toad-related incidents occur in the evening when cats or dogs lick or eat them. This can lead to signs including hypersalivation (dribbling), frothing, foaming, oral pain, vomiting, wobbliness, shaking, an increase in body temperature and collapse. In severe cases convulsions can occur. You can thoroughly rinse your dog’s mouth out (don’t let them swallow the water) then contact your vet for further advice.

Autumn poisons

Conkers. Serious cases of poisoning are rare – ingestion can cause marked gastro-intestinal signs – drooling, retching, vomiting, diarrhoea and abdominal pain. The conker’s case and conkers themselves also present a risk by causing an intestinal blockage. Dogs usually vomit any ingested conkers quickly and treatment to control vomiting may be needed.

Anticoagulant rodenticides. Most, but not all, rodenticides in the UK contain anti-coagulant compounds that interfere with a rat’s ability to clot its own blood. One off exposure to products bought in garden centres often does not cause problems. However, repeated exposure to products or exposure to professional rodent baits can cause disruption to a dog’s blood clotting ability and result in massive haemorrhage (bleeding). The effects may be delayed for several days – blood-clotting (coagulation) tests are often needed to determine if a dog is at risk of developing problems. Treatment involves giving an antidote and in severe cases transfusions of plasma or whole blood.

Luminous necklaces. The chemical mixture within these necklaces is very irritating to the gums – commonly causing salivation (dribbing), frothing/foaming from the mouth, vomiting and stomach pain. Although the signs can look dramatic, ingestion is unlikely to cause significant problems.

Oak/acorns. Exposure to acorns in dogs is common in the autumn and winter months. The toxic ingredient is thought to be tannic acid, which can cause damage to the liver and kidneys. Signs include vomiting, diarrhoea (with or without blood), abdominal pain, inappetance and lethargy. Ingested acorns can also cause an intestinal blockage.

Winter and Christmas poisons

Food hazards. Chocolate, onions, nuts, blue cheese, fruit cakes, puddings and mince pies can all be toxic to dogs. Watch out for turkey bones as these can cause choking, constipation or cause damage to your dog’s intestines.

Christmas trees and plants. Most species are low toxicity but may cause a mild gastrointestinal upset (vomiting and/or diarrhoea) if chewed. Tinsel and decorations can cause intestinal blockages if eaten and your pet may get a nasty shock if they chew through the electrical cable for your Christmas lights. Holly, mistletoe and poinsettia are all toxic to dogs so keep them out of their reach.

Batteries. Ingestion of batteries is more common at this time of year. If the battery is chewed and pierced it can cause chemical burns and heavy metal poisoning. If they are swallowed whole it is possible they will cause a blockage. All batteries are potentially toxic so if you suspect your dog has chewed or swallowed a battery speak to your local vet.

Antifreeze. Ethylene glycol (anti freeze) ingestion is very dangerous. It is sweet-tasting and very palatable. Even a relatively small quantity can cause serious kidney damage and can be fatal. Unfortunately the longer the delay between ingestion of the anti freeze and initiation of treatment the less favourable the prognosis.

All year round

Non-steroidal anti-inflammatory drugs (NSAIDs). NSAIDs are used for pain relief. Many human products are available over-the-counter, such as paracetamol, ibuprofen, diclofenac, naproxen or aspirin. Human NSAIDs can be toxic to all animals, but particularly to dogs where they can cause severe stomach ulceration and acute kidney or liver failure. Please do be very careful and always consult your vet before giving your dog any form of medication.

Animal NSAIDs are commonly used in veterinary medicine with trade names including Metacam and Previcox. Many of these have been made palatable to assist owners in giving medications to their pets. However if your pet gets hold of the medication they can eat more than they should. In cases of poisoning or overdose, toxic effects develop quickly and include persistent vomiting, vomiting blood, diarrhoea, and abdominal tenderness. Weakness and depression are often noted, though some animals show no signs of pain. Gastric (stomach) ulceration can occur without other clinical signs being present. Kidney damage is usually delayed by up to five days after poisoning and animals that are already unwell, dehydrated or with poor kidney function are at greater risk of toxic effects.

Vitamin D. Vitamin D compounds (calciferol, calcipotriol, calcitriol, cholecalciferol, tacalcitol, alfacalcidol and paricalcitol) are present in a wide variety of products. Examples include vitamin supplements, cod liver oil, rodenticides and feed additives. In human medicine they are commonly used in psoriasis treatments and vitamin D deficiencies. Veterinary uses include control of low blood calcium in cats and dogs with kidney disease. All vitamin D compounds are potentially toxic to dogs. Signs of toxicity depend on the compound and amount ingested, in the case of calcipotriol, calcitriol and tacalcitol signs may be seen within six hours and include weakness and lethargy, depression, increased water intake and increased urine output, profuse vomiting and diarrhoea. Signs progress to wobbliness, arching of the back, muscle spasms, and twitching. Fatal cases do occur, especially in dogs following ingestion of human psoriasis creams, however effective treatments are available in animals that have not developed advanced poisoning.

Mushrooms. The most common account of poisoning is by the mushroom Amanita phalloides, which is extremely toxic. Signs include mild vomiting and diarrhoea and can lead to more severe digestive problems, neurological (brain/nerve) disorders and liver disease.

Salt. Common products that are very high in salt include – sterilising fluids, water softeners, dishwasher salt, rock salt (used to de-ice roads) and some bath products (e.g. dead sea salt, bath salt), stock cubes, homemade play-doh and gravy powders. Salt (sodium chloride) toxicity is extremely dangerous and potentially fatal – a toxic dose may be as little as 1/16th of a teaspoon per kg of body weight. Do not attempt to make your dog sick (following ingestion of a poison) using salt water, it can cause severe problems and interfere with the treatment your dog needs.

This advice is not a substitute for a proper consultation with a vet and is only intended as a guide. Please contact the practice for advice or treatment immediately if you are worried about your pet’s health – even if we are closed, they will always have an out of hours service available.