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Poison Information and Advice

Toxic items that could harm your pet

What to do if you think your pet has been poisoned?

Phone the vet.  Don't take any chances. If there is an uncertainty as the amount or type of poison eaten then it is probably best for the pet to be seen and ideally to bring the product eaten (and any relevant information) to the practice.  We subscribe to an Veterinary Poison Information Service and have access to advice on a range of substances that your pet may have consumed.  Its very likely your pet is not the first to have eaten something strange.

We can often induce vomiting (if it's indicated for that poison) and give activated charcoal which absorbs the poison from the gut and reduces it's absorbtion.


Chocolate contains cocoa beans or cocoa butter which in turn contain Theobromine and Caffeine (both are methylxanthines).  Dogs are very sensitive to the effects of methylxanthines.

Signs of toxicity include hyperactivity, increased heart rate, tremors, vomiting and diarrhoea, excessive thirst, lethargy and potential death.  The effects are dose dependent and the amount depends on the type of chocolate the animal eats. Generally the more bitter the chocolate the more toxic it is. Mild signs are seen at 20mg/kg, moderate signs at 40mg/kg, and severe signs above 60mg/kg    

This roughly equates to a West Highland White Terrier size dog eating 100g milk chocolate or 25g dark chocolate, and a Labrador size dog eating 500g milk chocolate or 50g dark chocolate.


A member of the Allium family - as are garlic, leeks, and shallots. They are contained in onion powder, cooked/raw onions, gravy granules, baby foods etc. They cause damage to red blood cells and result in anaemia (low blood count).  

  • Only low levels are required to cause toxicity, approx. 15-30mg/kg  
  • Cats are more sensitive than dogs

Macademia Nuts

Only dogs are affected. Signs include lethargy, weakness, vomiting, ataxia (unsteady gait), tremors, and hyperthermia (heatstroke). Approximately 20-40mg/kg are enough to cause a toxic effect and signs are seen within 3-12hrs of ingestion.

Rising bread dough

Dough rises in stomach due to the animals body heat. Ethanol (alcohol) is produced during the rising process. The signs that are seen are related to ethanol toxicity and foreign body obstruction.

Mouldy Food

Usually from scavenging food, it contains tremorgenic mycotoxins (a type of nerve toxin) that causes ataxia (unsteady gait), muscle tremors, and seizures (fits) which can last for several days.

Grapes, raisins, and sultanas

They can cause acute renal failure (kidney failure). The mechanism is unclear and the amount required to cause toxicity is unknown. It seems that not every dog or cat is susceptible to the effects of the grapes/raisins. It is also thought that dried fruit is more toxic than raw fruit.Research is ongoing within the veterinary profession to investigate this further.

  • Toxic dose: Grapes 0.77oz/kg.  Raisins/Sultanas 0.11oz/kg
  • A 500g bag of raisins can cause kidney failure in a 30kg dog


Dogs can tolerate paracetamol  however 100mg/kg is toxic to the liver.  Cats are extremely susceptible to the effects and can show signs of toxicity from a single dose.

Never use paracetamol in your pets!

Tobacco Products

The toxic ingredient is nicotine.  25% of total nicotine content is found in cigarette butts. Dogs and cats require a minimal lethal dose of 20-100mg. Signs are seen 15-45mins post ingestion. These signs include excitation, rapid breathing, salivation, vomiting, diarrhoea, muscle weakness, twitching, depression, tachycardia (fast heart rate), collapse, coma, cardiac arrest.


These are anticoagulants (affect the bloods ability to clot), and are classed as short acting or long acting. Newer types have been developed due to rats developing resistance to the older drugs. Dogs and cats are susceptible to all types of anticoagulants. The body has a reserve of coagulant factors and signs of bleeding will not usually be seen for up to 72hrs, until these are all used up. Due to the variability of anticoagulants used in modern rat bait it is advisable to contact the surgery straight away. We can then contact the Veterinary Poisons Information Service to see if we would need to start treatment.

Slug pellets (Metaldehyde)

Symptoms are seen within 15mins-3hrs. Toxic dose is 20mg/kg. Signs of toxicity - anxiety, ataxia, muscle tremors, panting, seizures, hyperthermia, respiratory failure and death. The pet may survive the initial stages of poisoning but to succumb to organ failure in the next 3-5 days.  


  • Poinsettia causes irritation of the mouth, vomiting/diarrhoea, itchy skin
  • English Holly causes nausea, vomiting, diarrhoea
  • Lilies cause depression, decreased urination, and kidney failure in cats
  • Christmas Rose causes pain in the mouth and abdomen, nausea, vomiting, diarrhoea, and heart rhythm disturbance
  • Yew Trees cause trembling, muscle weakness, trouble breathing and heart rhythm disturbance. They can result in sudden death

This is just the tip of the iceberg.