Why do dogs sleep with their eyes open?
It can be worrying and a little disconcerting to find your dog sleeping with their eyes open, but is this really a cause for concern? Maybe you have noticed your new puppy sleeping with their eyes open and you aren’t sure if this is normal.
The good news is that in most cases finding your dog snoring with his eyes open isn’t something to worry about. However, there are some more serious conditions in which sleeping with the eyes open can be a symptom and it can be useful to be aware of this as a dog owner.
So if you are wondering “Do dogs sleep with their eyes open?” read on to find out more!
Table of Contents
Is it normal for dogs to sleep with their eyes open?
Like humans, most dogs sleep with their eyes closed. However, in some circumstances, it can be normal for a dog to sleep with their eyes open.
Sometimes you may notice your dog sleeping with his eyes partly open, however it probably isn’t his eyeball you can see. Dogs have a third eyelid- called a nictitating membrane- that automatically closes across the eyeball when the eyes close.
When the dog opens his eyes, the nictitating membrane automatically opens. The purpose of this membrane is to distribute tears and keep the eye moist, to provide protection and to move any debris to the corner of the eye.
When a dog sleeps with its eyes partly open, the nictitating membrane is likely to be closed and this is probably what you can see. If the dog did not have a nictitating membrane and slept with its eyes open, the eye would soon dry out and become irritated.
Your dog’s eyes may open during REM sleep
During Rapid Eye Movement (REM) sleep, the dog’s brain processes information that it has taken in during the day. During this sleep stage, you may notice your dog twitching, whining, wagging their tail, and even ‘running’ in his sleep.
His eyes will often move around and they may be partly open or may open and close momentarily.
If you notice your dog sleeping with its eyes open, blinking a lot or opening the eyes for a brief moment during REM sleep this is not usually something to worry about and it should subside when your dog moves into the next sleep stage.
His eyes should not be open for long enough to cause a problem.
Eyes open during anesthesia
Most dog owners will not get the chance to observe their dog under anesthetic, but ask any vet and they will tell you that it’s very common for anaesthetised dogs to sleep with their eyes open.
The vet team uses lubrication to ensure that the dog’s eyes do not dry out during the procedure.
Do dogs sleep with their eyes open - final thoughts
So, can dogs sleep with their eyes open? Yes and no. If the dog is sleeping with its eyes partly open, the nictitating membrane is probably closed to protect the eye.
A dog’s eyes would become dry and irritated if they were kept open for an extended period without blinking, so if the eyes are fully open, the dog probably isn’t asleep.
Most of the time, a dog sleeping with its eyes open a little isn’t something to worry about. The key is to know what is normal for your dog, so if you suddenly notice him sleeping with his eyes open for no obvious reason (REM sleep for example) it would be a good idea to chat to your vet.
Owners of breeds that are more prone to eye problems should be particularly vigilant. Contact your vet if you notice your dog sleeping with his eyes open more frequently than usual, if he has eye discharge or if his eyes look sore and irritated.
Suggested reading: Why do dogs sleep on their backs?