What is eye sleep?

Many people refer to the collection of mucus which builds up in the corner of the eyes overnight as ‘sleep’, but the medical term for it is call rheum.

During the day time we blink around 20 times per minute. Blinking is a way for your eyes to stay protected and moist. Each blink helps cover the eyes in protective oils and helps remove of any mucus, dirt, dust or any other foreign body from the eyes. While during our waking hours eye rheum is usually minimal, overnight while we sleep this increases as our eyes aren’t blinking to get rid of any mucus, therefore when we wake up we find we have more eye sleep in the corners of the eyes than during the day time. Most of the time eye sleep is normal and a natural process, but there are some instances where a build-up of eye mucus and eye discharge can be a sign of something else.

Eye Infection

There are so many types of eye infections that would cause your eyes to procedure more mucus than normal. One of the most common eye infections is conjunctivitis. Most people have heard of this eye infection and it can affect both adults and children. Conjunctivitis can be caused by allergies or a bacterial or viral infection. This infection makes the whites of the eyes looks red and a lot of discharge can be produced. Overnight, when we aren’t blinking, this discharge dries and gets crusty on the corners of the eyes and eye lashes. For many people using a course of eye drops will get rid of conjunctivitis, but you should always follow the advice of your eye doctor when using any drops for an eye infection. Eye infections can also happen following eye surgeries, such as laser vision correction, intraocular lens implants or corneal surgeries to name a few. If you have had eye surgery and start to notice a large amount of discharge coming from the eye, contact your ophthalmologist to seek medical advice.

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Dry Eye Disease

The eye procedures tears which acts as a barrier in protecting the eyes. Tears are made up of a fine balance of oil, water, mucus and antibodies. If these components are off balance or if the glands that help procedure the tears are not working correctly, then you will have some degree of dry eye disease. When your eyes are dry and not getting the normal about of fluid to protect and lubricate them, the body produces emergency tears. These back up tears don’t have the correct balance of oil, water, mucus and antibodies as regular tears, and if they have too much mucus then this can develop into extra eye mucus in the corner of the eyes during the day time, as well as at night time. Dry eye disease is a serious eye condition and seeking specialist advice before it gets worse is advisable.

Blocked Tear Ducts

Tears come from small glands located above the eyes. These tears then move down and across the eye and are drained into two small ducts on the upper corner and lower corner of each eye. If one or both of the drainage ducts are blocked, the tears don’t have anywhere to go, and this can cause watery eyes, irritation and infection. This infection, and infection of the blocked tear duct, causes discharge in the eye. Blocked tear ducts can be common in newborn babies, estimated at around 20% of newborn babies have a blocked tear duct, but this usually corrects itself within about 4-6 months. In adults, blocked tear ducts can be a result of swelling, injury or infection. If the blocked tear duct does not reopen on its own and becomes problematic, an eye doctor may suggest surgery to reopen the duct.

The above are only 3 examples of why the eyes may develop an excess amount of mucus, so if you start to notice your eyes are producing more sleep than normal it is best to get it checked out at your local eye clinic to make sure it is nothing to worry about.

About the expert

Mr Samer Hamada | Consultant Ophthalmologist and Corneal Surgeon

MD, MSc, DO (hons), FRCSEd, FRCOphth

I am Samer Hamada, founder and consultant ophthalmic surgeon with over 20 years’ experience in ophthalmology. I am a world-renowned specialist in cornea, cataract and refractive surgery. I’m not only a leading surgeon but also the only dual fellowship trained in corneal diseases in children from reputable institutions in the UK.

At Eye Clinic London I work closely with other consultant ophthalmologists, optometrists and orthoptists to achieve the best outcomes for our patients. Our main aim is to make sure our patients get the safest and best treatments available to them. We put your safety before anything else so you can rest assured that if you choose us you will be in the best and safest hands.

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