Sleepy Eyes: All-Day Sleepiness Explained

Do you often wake up with a crusty substance in the corners of your eyes? If so, you're not alone. This phenomenon, known as sleep in your eyes, is a common occurrence that happens while you sleep. Sleep in your eyes, or rheum, is a combination of mucus, oils, skin cells, and other debris that accumulates in the corner of your eyes due to a lack of blinking during sleep. While it may be unsightly and uncomfortable, rheum is typically harmless and is a natural part of healthy eye function. However, if you notice changes in colour, consistency, or quantity, it could be a sign of an eye infection or other eye-related issues.

Eye discharge is a protective function, removing waste and debris from the tear film and eye surface

Eye discharge, or "sleep" in your eyes, is a completely normal occurrence and is part of a healthy eye's protective function. It is a combination of mucus, oil, skin cells and other debris that collects in the corner of your eye while you sleep. This substance, called rheum, has a vital role in maintaining eye health.

Throughout the day, your eyes produce a continuous thin film of tears, which, when you blink, washes away any rheum before it hardens. This process ensures your eyes remain lubricated and free from harmful debris and bacteria. The tear film consists of three layers, each with a specific function. The first is the glycocalyx layer, a mucus coating that attracts water, allowing for the even distribution of the second layer. This second layer is a water-based tear solution, which is extremely thin, measuring only four micrometres thick. Despite its size, it is crucial for keeping eyes lubricated and washing away potential infections. The final layer is an outer layer of meibum, an oily substance composed of lipids such as fatty acids and cholesterol.

When you sleep, you are not blinking, so the rheum is not washed away and instead collects and dries in the corners of your eyes, forming a crust. This crust, or "sleep", is simply residue from the eye's protective process. It is usually white or light yellow in colour and may be wet and sticky or dry and crusty, depending on how much liquid has evaporated.

While a small amount of eye discharge is normal, if you notice a change in colour (such as green or yellow discharge), consistency or quantity, it could indicate an eye infection or other eye disease, and you should consult an eye doctor.

Sleep in the eyes is a combination of mucus, oil, skin cells, and other debris

"Sleep" in the eyes, or "eye sleep", is a common occurrence and refers to the crusting or gunk that forms in the eyes overnight. It is a combination of mucus, oil, skin cells, and other debris. This substance, also known as rheum, is a completely normal part of the eye's protective process.

The eye's tear film has three components that work together to ensure the eye is adequately hydrated. The first is the glycocalyx layer, which is composed mostly of mucus and coats the cornea, attracting water. This allows for the even distribution of the second layer: a water-based tear solution. The final layer is an oily substance called meibum, which is made up of lipids like fatty acids and cholesterol. Throughout the day, blinking washes away any excess eye discharge, but this collects overnight when the eyes are closed for a long period.

Rheum comes in a variety of consistencies and colours, depending on how much of it has evaporated and on its exact composition. It is typically clear or light yellow, and can be hard, sludgy, or thin. However, if the rheum is very thick, green, dark yellow, or accompanied by pain or redness in the eyes, it may be a sign of an eye infection.

To safely remove rheum, it is important to first wash your hands. Then, use a warm flannel or compress. If the eyelashes are stuck together, soak the closed eye under a warm, damp compress and gently wipe away the rheum.

It can be wet and sticky or dry and crusty, depending on how much liquid has evaporated

The "sleep" in your eyes, or "rheum", is a combination of mucus, oil, skin cells, and other debris that accumulates in the corner of your eye while you sleep. It is a natural part of healthy eye function, and its consistency varies from wet and sticky to dry and crusty, depending on how much liquid has evaporated from it.

Throughout the day, your eyes produce mucus, and a continuous thin film of tears bathes the eyes when you blink, flushing out the rheum before it hardens. However, when you sleep, you are not blinking, and the rheum collects and crusts in the corners of your eyes and sometimes along the lash line. This is why you may find "sleep" in your eyes when you wake up in the morning.

The amount of "sleep" in your eyes can vary depending on several factors. For example, during allergy season or when your eyes are dry, you may notice more rheum. Additionally, if you wear contact lenses, you may experience an increase in eye discharge due to various reasons, including a contact lens-related eye infection or discomfort from dry and irritated eyes.

While a small amount of eye discharge is normal and harmless, excessive eye discharge, especially if it is green or yellow and accompanied by other symptoms such as blurry vision, light sensitivity, or eye pain, can indicate a serious eye infection or eye disease. In such cases, it is important to consult an eye doctor promptly for an accurate diagnosis and treatment.

Sleep in the eyes is called rheum and is a normal part of a good night's sleep

Sleep in the eyes, or "eye sleep", is the result of a combination of mucus, oil, skin cells, and other debris that accumulates in the corner of the eye while we sleep. This substance, called rheum, is a normal and healthy part of a good night's sleep. It is the result of the eye's protective process, which keeps the eyes lubricated and washes away potential infections.

Throughout the day, the eye's tear film keeps the eyes hydrated and removes harmful debris and bacteria. The tear film has three components: the glycocalyx layer, a water-based tear solution, and an outer layer of oily substance called meibum. When we are awake, we blink away any excess eye discharge, but this collects overnight when our eyes are closed for a long period. Additionally, sleep relaxes the meibomian gland ducts, causing more of the tear film's oily substance to enter the eye.

Rheum comes in a variety of consistencies and colours, depending on how much of it has evaporated overnight and its specific composition. Small amounts of eye sleep are perfectly normal and should be yellowish or clear in colour. It can also be crusty and hard, more sticky and thin, or even watery. However, if you notice a change in colour, such as green or grey, or a change in consistency or quantity, it could indicate an eye infection or other eye conditions such as conjunctivitis, blepharitis, or a corneal ulcer.

While rheum is a normal occurrence, it is important to maintain good eye hygiene. To safely remove eye sleep, wash your hands first, and then use a warm flannel or compress. If your eyelashes are stuck together, soak your closed eye under a warm, damp compress and gently wipe away the rheum. Always wash your hands before and after touching your eyes to prevent the spread of any potential infection.

If the rheum is yellow or green, it could be bacterial conjunctivitis

Eye discharge, or "sleep" in your eyes, is a combination of mucus, oil, skin cells and other debris that accumulates in the corner of your eye while you sleep. This is completely normal and is just your eye's way of removing waste products and other harmful debris from the tear film and the front surface of your eyes.

However, if you notice a difference in consistency, colour and quantity of eye gunk, it could indicate an eye infection or disease.

Bacterial Conjunctivitis

Conjunctivitis is an inflammation of the conjunctiva, the thin membrane that lines the "white" of the eye (sclera) and the inner surface of the eyelids. It is often referred to as "pink eye" because it typically causes the eye to turn red or pink. Conjunctivitis can be viral, bacterial or allergenic.

If you suspect you have bacterial conjunctivitis, you should make an appointment with an eye doctor. They will likely prescribe antibiotic or antiviral eye drops and ointments.

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