Rat poisoning in dogs


  • Rat and mouse poisons (rodenticides) contain ingredients that are often highly toxic to dogs. They can cause internal bleeding, kidney failure, and even death if eaten by your dog.
  • Many rodenticides are mixed with sweet tasting ingredients in order to attract rats and mice, so are likely to smell like a tasty treat to your dog.
  • If you suspect your dog has swallowed rat or mouse poison, call your vet immediately – do not wait to see if symptoms develop.

Is rat poison harmful to dogs?

A photo of rat poison

There are several different types of rat poison and unfortunately, they are all harmful to dogs. Rat poisoning usually happens when your dog eats the poison directly, but is also possible if a dog eats a rat or mouse that has been poisoned (this is called secondary poisoning).

The most common type of rat and mouse poison used in the UK is:

  • Anticoagulants which prevent the blood from clotting leading to internal bleeding.

Other types of poisons include:

  • Cholecalciferol (vitamin D3) which causes sudden kidney failure and heart problems.
  • Bromethalin which causes brain swelling.
  • Zinc and aluminium phosphides which release toxic gas once in the stomach and stop cells from making energy, ultimately causing damage to the heart, brain, kidney and liver.
  • Strychnine which causes muscle spasms, paralysis and death.
  • Alphachloralose poisons which are becoming increasingly popular and have a negative effect on the central nervous system (brain and spinal cord).

Symptoms of rat poisoning in dogs

Symptoms of rat poisoning depends on how much, and the type of poison the dog has eaten.

Symptoms of internal bleeding from an anticoagulant poison can include:

Symptoms of other types of rat and mouse poisons can include:

It is important to remember that there can be a delay in how quickly your pet shows signs after eating some types of poisons, which can vary from minutes to up to ten days. Bleeding is not always obvious especially if it is happening inside the abdomen, chest, lungs, joints or gastrointestinal tract. If you suspect your dog has eaten poison, contact your vet straight away, don’t wait for symptoms to appear.



To make a prompt diagnosis, and start the correct treatment as quickly as possible, your vet will need to know the following:

  • When the poison was eaten.
  • The type of poison, brand name, and manufacturer - take the packaging with you (it can be really hard to tell the type of rat poison just by looking at it).
  • How much poison has been eaten – try to remember if the packet was full before your dog got to it, and bring in any remaining poison in a secure container.

Your vet may want to carry out the following diagnostic tests:

  • Blood tests - there may be more than one type of blood test, and some specialised tests to check for clotting problems may need to be sent to a lab.
  • X-rays and ultrasound scans to check for bleeding in the chest or abdomen (tummy), this may be at the time, and/or a few days later.

The timing of these tests may depend on when the poison was eaten.


Treatment depends on which poison your dog has eaten, how much they have eaten, and how long it’s been since they ate it. After determining these factors and after checking your dog over, your vet will decide on the best course of treatment.

This may include:

  • Making your dog sick (usually only effective if they ate the poison very recently)
  • Giving a black liquid called ‘activated charcoal’ to absorb toxins in the body (also usually only effective if they ate the poison recently)
  • Vitamin K medication – this is to help with blood clotting and is an effective treatment for certain types of poison, and if needed, tends to be given for several weeks and may be followed by a blood test at the end of the course of treatment.
  • Hospitalised care
  • Anti-seizure medication if they are having seizures
  • A fluid drip
  • In severe cases – oxygen therapy, blood transfusions

In the early stages of treatment and while recovering at home, if your dog has eaten anticoagulant poison it is really important to limit their activity to prevent internal bleeding.


Rat poison is extremely toxic. If your dog has mild symptoms and is treated quickly, they have a good chance of recovery. However, if they are showing severe symptoms, or if treatment is delayed, they are likely to have a worse outlook.


The best way to prevent your dog from ingesting rat poison, is to avoid using it in your own home, and by keeping your dog close by on walks to make sure you can see if they pick anything up. If you do choose to use it, make sure bait stations are somewhere your dog doesn’t have access to, and store any remaining poison well out of reach – remember there is still a risk of secondary poisoning if your dog eats a poisoned rodent.

When to contact your vet

If you suspect your dog has swallowed rat or mouse poison, call your vet immediately – do not wait to see if symptoms develop.


Treatment for rat poisoning can become very expensive, so it’s important to speak openly with your vet about the cost of treatment, your finances, and what you think is right for your dog.

Consider insuring your dog as soon as you get them, before any signs of illness start, to ensure you have financial support to care for them.


How long does it take for rat poison to affect a dog?

Many poisons are designed to act quickly, so your dog could become very unwell within an hour of eating it, or sometimes sooner. If your dog has eaten an anticoagulant rat poison, signs may not show until around 3-5 days.

Are there any dog-safe rat poisons?

There is unlikely to be a rat poison that won’t harm your dog if they eat it.

Can a dog die from eating a poisoned rat?

If your dog has eaten a rat or mouse that has recently been poisoned, there is a risk that they could be affected by the poison (secondary rat poisoning). If you suspect your dog has eaten a rat or mouse, contact your vet.

What does rat poison look like?

Rat poison can come in many different forms including pellets, blocks, granules and liquids; and it can be a variety of colours (including teal, blue, green or pink). The shape or colour of the poison cannot help you determine what type of poison it is, that is why it is important to have the packaging to hand if possible.

Published: September 2023

Written by vets and vet nurses. This advice is for UK pets only. Illustrations by Samantha Elmhurst.