Coming to the decision to have your dog put to sleep can be incredibly difficult. One of the most common concerns is whether euthanasia is painful for their dog. No one wants to put their dog through pain; but this reluctance could lead to a delayed euthanasia or even not having them put to sleep at all when they really need you to make that decision. Today we will ask whether dogs feel pain when they are put to sleep, to ease any of your concerns and help make that terrible decision a little easier.

How We Put Dogs to Sleep

Putting a dog to sleep can vary considerably depending on the vet, the owner and the individual animal. However, the vast majority of euthanasias are performed via an intravenous injection of a drug called pentobarbital. 

Pentobarbital is a drug that causes sedation, anaesthesia and can stop seizures

In fact, it was commonly used for these purposes decades ago, but has been superseded by safer more modern drugs. At higher doses it causes the heart and lungs to stop working, leading to rapid death. For most dogs, the drug will cause unconsciousness first, and then death as the heart and lungs stop. This can take as little as 30 seconds (though it can be prolonged in certain individuals). This means that your dog will be asleep before their body shuts down, so will not feel any distress or pain at the point of death. They are as asleep as they would be for a surgical procedure. 

As stated above, most vets will inject this drug directly into your dog’s vein so it reaches the heart quickly and does not prolong death. Commonly, this is done in your dog’s wrist vein though can be done in other surface veins too. The initial jab of the needle can be painful for some dogs but no more than any other needle injection. If a vet injects pentobarbital directly into the vein from a syringe, there is a chance the drug may leak out into surrounding tissue. The drug can sting so this can cause a pain response. The risk of leakage can be minimised by using an intravenous catheter and injecting the drug down a long drip line. Flushing either the catheter or syringe directly first can also confirm that they have been placed correctly. 

When correctly performed, for the vast majority of dogs the only pain felt will be a little prick as the needle goes in. Then they rapidly lose consciousness and will feel no more pain. 

Alternative Methods

In some cases, we are unable to inject into the veins and have to inject pentobarbital via other sites. This may be because your dog has poor circulation or fragile veins; they are too nervous, scared or aggressive to approach safely; or the veins cannot be accessed due to bandages, obesity or wounds.

Other common sites include into the kidneys, abdomen, muscle or heart. In most of these cases, we prefer to sedate your dog first (more on this later) so they are heavily drowsy or even fully anaesthetised. But this may not be possible if euthanasia must be performed quickly. All of these injection sites have the potential to hurt more than intravenous. They can also take longer for the drug to act, prolonging death. For this reason, most vets will only choose these sites if intravenous is not an option and will advise your dog is sedated first. 

Other Sources of Pain

As well as everything the vet is doing, there can be other aspects of a euthanasia that might be painful for your dog. 

Most dogs being put to sleep are very unwell or elderly, and usually in pain. Conditions like arthritis, cancer, kidney failure or breathing difficulties will all cause distress and/or pain. For some dogs, lying in certain positions or having to extend their legs for a catheter may cause discomfort. We can minimise this as much as possible by discussing how you would like the process to occur, providing soft blankets to lie on, administering pre-emptive pain relief or sedation, and choosing injection sites carefully.

There is also the emotional distress and pain that should be considered. 

As we have discussed in previous blogs, some dogs become distressed at the vets and by being touched. Others may be distressed if the owner is not present, or distressed if the owner is present but in great distress themselves. However, though it is unclear whether dogs understand what we are doing when we put them to sleep, the vast majority are comfortable and accept the process peacefully. In some cases, this is because they are so unwell and have little energy to react.

However, in both cases, pain is not caused directly by the euthanasia process, and being put to sleep will stop all of this pain. In most situations, the short physical and emotional discomfort of the euthanasia process is worth stopping other, more serious, forms of pain completely. Remember that euthanasia means ‘good death’, and that the primary goal is to prevent further suffering.

What Definitely Isn’t Pain

As a dog is put to sleep, you may notice some unusual reactions that could be easily confused with pain. Let’s go through these now.

Occasionally, as pentobarbital is injected, a dog may cry out or yelp loudly

This is obviously quite shocking and can be upsetting for owners and vets alike. But we do not think this is a pain reaction, but rather ‘dysphoria’. As the drugs kick in, it causes a brief period of excitement before it induces anaesthesia. It is not pain, just a reaction to the drug.

As your dog passes away, and sometimes even after the heart has stopped, your dog may take a few very deep gasping breaths

We call these agonal breaths or a ‘last gasp’ and it is a normal reaction to the body shutting down. As the heart stops, the body automatically tries to respond to the lack of oxygen by taking big breaths. Your dog is already asleep at this point, not feeling any pain, and may already be considered deceased.

Finally, as your dog passes away and their muscles start to relax, you may notice some twitching, movement or even paddling of the legs. They can also relax their bowels and bladder, causing weeing and pooing. They often will not close their eyes. Again, these are all normal signs that occur at death, and not signs of pain. 

A good vet should warn you well in advance that any of the above behaviours could occur, assure you that they are normal and your dog is not in pain. If they are prolonged, administering a little more pentobarbital can stop them quicker. 

How to Minimise Pain As Much As Possible

So, to summarise, there are aspects of being put to sleep that can be painful but on the whole it is not a painful process. There are steps we can take to minimise pain even more too.

Discussing euthanasia with you early is important, potentially weeks in advance with very old or terminally ill dogs, so you know what to expect. We can talk about steps to make it more comfortable, such as having a home visit, ensuring the family is there, including dog friends or toys, and so on. We can easily tailor most euthanasias to individual dogs.

During the process, ensuring we try and inject intravenously where possible is important, ideally using catheters and a drip line. If other sites are needed, sedation may be useful to minimise pain and distress. However, sedation may also make it more difficult for vets to access veins. Some owners do not like their dog being asleep for the process, so sedation is not appropriate in all cases. 

And we again want to reiterate that even in the most difficult, distressing or even painful euthanasias, they are always performed for a reason and not taken lightly. In almost all cases, the dog is suffering greatly and being put to sleep will stop this pain. Without euthanasia, many of these dogs would suffer for months or even years more, in much more pain than being put to sleep would cause. 

We sometimes have to choose the lesser of two evils and risk a little discomfort to stop suffering. But please remember that the vast majority of dogs put to sleep go peacefully, quickly and relatively painlessly.

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