When a pet passes, whether naturally or from euthanasia, they may experience a phenomenon called agonal breathing. Although these gasping breaths are simply a reflex that occurs as the brain shuts down, they can be mistaken for distress or suffering, which can lead pet owners to feel guilt or shame.

Knowing what to expect as a pet passes naturally or during euthanasia, including what agonal breaths are and what they mean, can help you feel more at ease with the process so you can focus on saying goodbye to your pet.  

Here, we explain agonal breathing in pets, why it happens, and what to do if your pet has difficulty breathing for any reason.

What does agonal breathing look like in pets?

As a pet passes, they often take several deep, long breaths. These are called agonal breaths. These breaths cause the pet’s chest to expand fully and then retract. Although the term agonal sounds like the word agony, rest assured that these breaths are not painful and don’t indicate that a pet is suffering in any way. 

Why does agonal breathing happen?

Agonal breathing in pets is caused by a reflex in the lower brainstem that can remain active for a short period after the brain has shut down. These final breaths are not under conscious control. They do not indicate that the pet is still alive in any meaningful sense or that they are aware of what’s happening.

When a pet dies, the body shuts down in stages instead of all at once. Higher brain functions, such as reasoning and consciousness, are lost first, followed by control of basic life functions, such as breathing. The brainstem may remain active for a few seconds or minutes after a pet appears to have passed, which can cause the final gasping breaths we call agonal breathing.

Agonal breaths don’t happen to every pet, but they are something you should prepare to see and understand. During euthanasia, pets may take only a few agonal breaths that pass quickly. During a natural death, agonal breathing may be prolonged. What’s important to remember is that pets are not conscious during these breaths, so they are not suffering.

What agonal breathing is not

During an emotional goodbye, it’s easy for pet owners unfamiliar with the dying process to misinterpret what’s happening to their pet during agonal breathing. Without context, it might seem like a pet is desperately gasping for air, trying to breathe, or “coming back to life” during euthanasia. 

However, agonal breathing in pets is not:

* A sign of pain or distress — The pet is not conscious or aware at this stage, so there is no perception of panic or discomfort.

* A sign that the euthanasia didn’t work — Agonal breathing can happen after your pet’s heart stops, but that doesn’t mean they will wake up.

* A sign that you waited too long or acted too soon — Agonal breaths are not a reflection on you or your pet’s care; they simply happen.

Understanding what agonal breathing is and isn’t can help you recognize it as a physical phenomenon that has no bearing on the euthanasia experience for you or your pet.

Agonal breathing during euthanasia

Most pet owners who choose euthanasia expect the process to be peaceful and quiet. And in most cases, this is true. However, some pets experience physical changes during the final moments of life, such as agonal breathing, despite everything else going “right.”

During euthanasia, the veterinarian first gives a sedative to help your pet relax. Once your pet is asleep, the vet gives a second injection that stops the heart. Most pets lose consciousness quickly and are not aware of any physical pain or discomfort in the moments that follow. 

Agonal breathing, gasping, a big stretch, or small muscle twitches can occur in the seconds between injection and death as the nervous system continues to send signals to the body. The sedative given to your pet can help minimize these movements so your pet’s passing feels peaceful and calm.  

Remember that these are not signs of pain or distress, and they do not mean your pet is still alive. The veterinarian performing the euthanasia will stay with you during this time to answer any questions, explain what is happening at each step, and confirm when your pet has passed.

Agonal breathing during natural death

A natural death in pets usually takes much longer than euthanasia. Some physical reactions pets may experience during the minutes, hours, or sometimes days before dying include:

* Slow or irregular breathing

* Intermittent or prolonged agonal breathing

* A sigh, groan, or airway rattle

* Stretching of the neck and limbs 

A natural death can be difficult for many pet parents to watch and painful or uncomfortable for the pet. Depending on the pet’s specific health conditions, most veterinarians recommend humane euthanasia to quickly alleviate pain and suffering and prevent prolonged death when quality of life declines. 

Still, some families choose natural death because of their beliefs. In other cases, a pet passes before the family can make a decision. A hospice veterinarian can prescribe pain medications or sedatives you can give your pet in the days or hours leading up to their death to reduce any distress and help your pet relax, but agonal breathing may still occur.

A Lap of Love veterinarian can explain what to expect during a natural death, given your pet’s unique circumstances, and help you decide if and when in-home pet euthanasia might be right for you and your family.

Agonal breathing and the pet loss experience

Seeing your pet take a final, agonal breath can trigger feelings of guilt or regret. You may question if you made the right choices in your pet’s treatment and replay moments in your mind. For some pet owners, agonal breathing is the detail that bothers them most.

Understanding agonal breathing in pets as a physical, involuntary phenomenon, similar to a muscle twitch, can help you put your memories into perspective. Consider talking to a pet loss grief counselor or support group if you need help understanding your thoughts and feelings and working through them in a healthy way.

Agonal breathing versus dyspnea

Pet owners should know the difference between agonal breathing in pets, which occurs only in a pet’s final moments or hours, and trouble breathing (i.e., dyspnea) caused by a medical condition. Many breathing problems are treatable and unrelated to the dying process. 

If your pet’s breathing seems off and you aren’t sure why, call your veterinarian or seek emergency care. Even for pets with terminal illnesses like heart disease or cancer, treatment may help improve or stabilize breathing difficulties for several weeks or months.

If your pet’s condition is deteriorating quickly or you believe your pet is experiencing agonal breathing at home, check in with your pet’s veterinary team or Lap of Love hospice veterinarian to determine whether comfort care or in-home pet euthanasia is the right option.

Final breaths

Witnessing the final moments of a beloved pet’s life, especially when something unexpected happens, can be intense and upsetting. Agonal breathing is a normal physiological response to death, and does not indicate a pet is suffering or in pain. Understanding this can help make the process less stressful for pet owners.

Choosing humane euthanasia over a natural death can help to minimize agonal breathing and ensure pets pass quickly and peacefully on your family’s terms. Contact your local Lap of Love veterinarian to learn more about in-home euthanasia services, pet hospice care, and what to expect during the pet aging and euthanasia process.