Mainly many dogs sleep with their eyes open; it is pretty standard and found many breeds of dogs its nothing to get worried or surprised about it if you see your dog is sleeping with their eyes open.

Dog’s have natural eye protection.

Maybe you get worried if your dog is sleeping with open eyes; you might think they get dust goes inside the eyes.

but actually, that’s not true because dogs have natural eye protection (third inner eyelid), also called the nictitating membrane, that sits below their normal eyelid.

They might not be sleeping, just lazy. 

Many times dogs are not sleeping with open eyes; when you see your dog is lazy or breathing heavily, they might get tired and take rest but not sleeping they notice every activity goes around their 

Should I wake up my dog?

If you see your dog is sleeping with open eyes, then you should be careful by waking them up 

waking dogs from deep sleep can shock them or depress them, which can also disturb them sometimes; they stop eating their meals for days

also, if they are dreaming about chasing or hunting their prey and that time you try to wake up them, they might accidentally clamp or bite your arms which is not their fault, and you can’t blame them for that 

When should I get worried about it? 

There are some circumstances in which you notice your dog is sleeping with open eyes is regular or a condition of the medical state.

A variety of symptoms accompanies these conditions. The average adult dogs sleep 8 to 13 hours a day which might be different in some breeds; they can also suffer dogs from Narcolepsy like human beings; if your dog’s sleeping pattern is changed or disturbed, they fall asleep at the wrong time, then you should concert your vet.