Understanding Dog Nightmares: Causes, Signs, and How to Help

This pet health content about Dog Nightmares was written by a veterinarian, Dr. Debora Lichtenberg, VMD. This article was originally published in 2013 and is regularly updated. It was last reviewed for accuracy and updated March 24, 2026

If you have questions or concerns, call your vet, who is best equipped to ensure the health and well-being of your pet. This article is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. See additional information.

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When I was just starting out as a veterinarian, a friend told me her dog was having nightmares. The dog was twitching violently, vocalizing, and thrashing during sleep. At the time, I had almost no clinical framework for what I was seeing. What I now recognize as classic signs of dog nightmares associated with REM sleep disorder was, back then, a medical mystery.

Dog nightmares are more common than most pet owners realize. Most dogs twitch, paddle their legs, or make small sounds during sleep. That is normal. But some dogs experience something far more intense, and knowing the difference matters.

Understanding Dog Nightmares and REM Sleep Disorders

Dogs definitely dream. Most people have observed their dog twitching, doing a tiny paddling motion, or quietly vocalizing during sleep. This is common behavior.

However, some dogs experience true sleep disturbances. These dogs may exhibit extreme behaviors during deep sleep, such as growling, screaming as if in pain, or even aggressive behavior.

• Veterinary behaviorists and neurologists believe these dogs suffer from a true sleep disturbance that occurs during REM sleep.
• Most people who observe these terrifying sleep disorders naturally think their dog is having a nightmare, a night terror, or even a seizure.

If these episodes occur only during sleep, if you can usually wake the dog up with strong voice commands, and if the dog is neurologically normal during waking hours, then this is not a seizure disorder.

Veterinarians classify these conditions not as dog nightmares or seizures but as REM sleep disorders.

What to Do If Your Dog Is Having Nightmares

If you observe frightening behavior in your dog during sleep, the first step is to try waking the dog up using your voice. It is important not to touch or shake the dog, as this could startle them and result in a bite.

• Use your voice to wake the dog, avoiding physical contact.

Taking a video of the sleep disorder can be helpful to show your vet. For particularly violent episodes, consider using a crate, even a padded one, as a temporary safeguard.

• Take videos of the sleep disorder and any unusual behavior.
• Consider using a crate for safety during violent episodes.

Being observant of your dog's behavior both while sleeping and awake is crucial. If you notice anything unusual, document it on video.

Once you have gathered enough observations, make an appointment with your vet to discuss the problem and show the videos. This will help rule out any medical issues that may be causing the behavior. In some cases, your vet might recommend consulting with veterinary specialists.

It is also worth thinking about where your dog sleeps during this time. A consistent, secure spot can reduce the intensity of episodes and make it easier to monitor your dog overnight. If your dog has been sleeping in bed with you, it may be worth reconsidering that arrangement until the episodes are better understood. To summarize, here is what you should do:

• Use your voice to wake the dog, avoiding physical contact.
• Take videos of the sleep disorder and any unusual behavior.
• Consider using a crate for safety during violent episodes.

A Terrifying Experience

As a veterinarian, I often hear from pet owners that witnessing an intense sleep disorder episode in their dog was a frightening experience. “It freaked me out!” is a common sentiment. During these episodes, dogs can: Scream as if they are in intense pain

• Exhibit violent limb movements or even run throughout the house.
• Howl, bark, growl, or chew, and in extreme cases, they might bite themselves or others.

Some dogs have even been known to chase or “pin” humans or other animals during these episodes. The intensity and frequency of these episodes can vary significantly from dog to dog, making each case unique and sometimes challenging to manage.

For a visual guide on how to handle dog nightmares, check out this helpful video

Dog Nightmares: What We Know and Don't Know

Veterinary neurologists believe these episodes are rapid eye movement (REM) sleep disorders, which are commonly associated with dog nightmares.

REM sleep disorders occur in people and have been extensively studied. However, this is a more challenging disorder to study in dogs, but some research has been conducted.

The big difference between people and dogs is that people often develop this syndrome as they get older. But in dogs, REM sleep disorder often occurs in young dogs, which can be very troubling for the people caring for these puppies.

In one of the few studies conducted, 64% of sleep disorder dogs were 1 year old or less.

Causes of REM Sleep Behavior Disorders in Dogs

The exact causes of REM sleep behavior disorders in dogs are unknown. In humans, REM sleep disorders often occur later in life and can precede degenerative neurologic diseases such as Parkinson’s disease. It seems to be a different phenomenon in dogs since the average age of onset is so young.

Studies suggest possible causes of sleep disorders in dogs may include: Congenital: The puppy was born with it.

• Neoplastic: Cancer that affects the brain or neurological system.
• Infectious: A primary brain infection or any infection in the body that crosses the “blood–brain barrier” and infects the brain. This could be bacterial, viral, or fungal.
• Degenerative: A degenerative brain disorder that leads to decreased brain function, like dementia or senility, similar to Parkinson’s in people.
• Idiopathic: Not traceable to a direct cause.
• Vascular: A disruption in normal blood flow to the brain, similar to a stroke or transient ischemic attack (TIA, or ministroke) in people.
• Traumatic: Head injury, for example.

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Diagnosis of REM Sleep Disorder

Diagnosing REM sleep disorder in a dog is not easy.

• An electroencephalogram (EEG) can demonstrate that the sleep-associated episodes occur during REM sleep, supporting a diagnosis of an REM behavior disorder.
• Other brain imaging is necessary to rule out primary brain changes.

All of these tests require referral to a veterinary neurologist.

Vets usually diagnose REM sleep disorders using these tools:

• Perform a thorough neurologic exam and get basic blood work, which should be normal.
• Get a detailed history and videos from the pet parent. As mentioned earlier, if the pet is neurologically and behaviorally normal in every other way except while sleeping, it is most likely an REM sleep disorder.
• Refer to a veterinary neurologist and/or behaviorist if the case is confusing or severe. Some people may be unsure if their pet is normal while awake or might think they have observed seizure-like activity in addition to the sleep disorder.

Dual Diagnosis

Seizure disorders and behavioral problems are fairly common in dogs. So it's possible that a dog could have multiple conditions, making a diagnosis of REM sleep disorder more complicated.

Several case reports of dual diagnoses exist. After thorough neurologic and behavioral work-ups, pups have been diagnosed with REM sleep disorders as well as seizure disorders, behavioral problems, obsessive-compulsive disorder, etc.

Most experts do not believe there is a correlation between REM sleep disorders and other neurologic or behavioral disorders, but more studies need to be done.

Treatment of REM Sleep Disorder

Remember that this disorder varies greatly from dog to dog. Treatment depends on the severity of the condition and how the dog's person is dealing with the problem.

Mild Episodes

If the episodes of the sleep disturbance are infrequent, not very intense or severe, not threatening to humans or other animals, and not disturbing the peace of the household, many people elect to have the dog sleep in a comfortable crate, padded if necessary, or a secure sleeping space.

• Mild episodes themselves are not dangerous to the pet, so conservative treatment is an acceptable option.

Severe Episodes

More severe cases usually require drug therapy. Severity is indicated when: Episodes occur nightly or multiple times a night.

• The episodes are intense or intensifying with time.
• The dog harms itself or others during episodes.
• The dog cannot be contained in the environment.

Drugs that have proved most effective in treating REM sleep disorders in dogs include: Potassium bromide: an anti-seizure medication. Clonazepam: a benzodiazepine.

• Learn more about how dogs can develop a tolerance to benzodiazepines.

Dogs, like humans, can develop a tolerance to benzodiazepines, so many vets reach for potassium bromide first.

Response to Drug Therapy

The response to drug therapy varies, just like the disorder:

• Some dogs have their sleep disturbances completely controlled.
• Others still have episodes, but they are less intense or less frequent.
• Rarely is there no improvement at all.

If a combination of drugs does not relieve symptoms, it’s time to look further for an answer. There may be an underlying brain lesion.

Selective serotonin reuptake inhibitors (SSRIs) have been tried and may work in some cases — but some dogs actually get worse on an SSRI. This is true in people as well.

How to Comfort Your Dog During a Nightmare

If you notice your dog experiencing a nightmare, it's essential to approach the situation with care. Dog nightmares can be distressing for both the pet and the owner, but there are ways to comfort your dog without causing additional stress.

• Stay calm: Your dog can pick up on your emotions, so staying calm and composed is crucial.
• Use a soothing voice: Gently call your dog's name or speak in a soft, reassuring tone. This can help bring your dog out of the nightmare without startling them.
• Avoid physical contact: As much as you may want to reach out and comfort your dog, it’s best not to touch or shake them during a nightmare. Physical contact could startle your dog, leading to an unintended bite or increased anxiety.
• Create a safe environment: Ensure your dog’s sleeping area is comfortable and secure. A familiar blanket or a favorite toy nearby can help create a sense of safety and comfort, reducing the intensity of dog nightmares.

If dog nightmares are a frequent occurrence, consider consulting with your vet for further advice and possible treatment options to help alleviate the issue.

Comfort plays a big role in reducing dog nightmares and helping your pup sleep soundly. An orthopedic pet bed, like the one from Noah and Paw, can provide extra support and security. Learn more in our Noah and Paw Editorial Spotlight to see if it’s the right fit for your dog.

Can Nightmares Affect Your Dog's Overall Health?

While dog nightmares are generally not harmful, frequent and intense nightmares can potentially affect your dog's overall health. Here’s how:

• Sleep disruption: Repeated episodes of dog nightmares can lead to disrupted sleep patterns, which may affect your dog’s mood, energy levels, and overall well-being.
• Stress and anxiety: Experiencing frequent nightmares may increase your dog's anxiety, leading to stress-related behaviors such as excessive barking, whining, or destructive behavior.
• Physical injury: In severe cases, a dog might injure itself during a particularly intense nightmare, especially if they are thrashing around or attempting to run in their sleep.

If you observe any signs of stress, anxiety, or physical harm in your dog related to dog nightmares, it’s crucial to consult with a veterinarian. They can assess whether the nightmares are a symptom of a more significant underlying issue and recommend appropriate interventions.

My First Case of REM Sleep Disorder

In 1990, I encountered my first case of what I now recognize as REM sleep disorder in dogs. A friend’s middle-aged rescue dog, Chica, was frequently experiencing violent nightmares shortly after being adopted.

At the time, little was known about sleep disorders in dogs, and recording these episodes was challenging without the technology we have today. My friend described how Chica, normally calm and peaceful, would thrash around and even attempt to bite during these episodes.

Recognizing the severity of the situation, I referred her to the Cummings School of Veterinary Medicine at Tufts University, where she received a proper diagnosis.

This case taught me important lessons as a veterinarian:

• Take pet parents seriously: Even if a complaint seems unusual, it’s crucial to listen. Pet owners know their animals best.
• Approach with humility: The field of veterinary medicine is always evolving. Keeping an open mind helps us better serve our clients and their pets.

If your dog seems to be having nightmares, keep your phone ready to record, or consider using a nanny cam to capture these episodes. In these cases, a video is worth a thousand words.

Frequently Asked Questions (FAQ)

References

• Coren, Stanley, PhD, DSc, FRSC. "Do Dogs Dream?" Psychology Today. Oct. 28, 2010. https://www.psychologytoday.com/us/blog/canine-corner/201010/do-dogs-dream
• Bush, William, VMD, DACVIM, et al. "Diagnosis of Rapid Eye Movement Sleep Disorder With Electroencephalography and Treatment With Tricyclic Antidepressants in a Dog." Journal of the American Animal Hospital Association 40, no. 6 (November-December 2004): 495-500. https://pubmed.ncbi.nlm.nih.gov/15533971/
• Calder, Christine D., DVM, DACVB. "A Case Report: REM Sleep Behavior Disorder in a Jack Russell Terrier." American College of Veterinary Behaviorists Veterinary Behavior Symposium, 2017.
• Overall, Karen, VMD, PhD, DACVB, CAAB. Manual of Clinical Behavioral Medicine for Dogs and Cats. Elsevier. 2013.
• Schenck, C.H., and Mahowald, M.W. "REM Sleep Behavior Disorder: Clinical, Developmental, and Neuroscience Perspectives." Sleep, 25(2), 2002. https://pubmed.ncbi.nlm.nih.gov/11902427/