Share on Pinterest
Phevos Theodoridis/EyeEm/Getty Images

Picture this: Dawn is breaking, and it’s time to wake up. You reach over to quiet your alarm clock, stretch your arms to greet the day, and attempt to open your sleepy eyes… only to find your eyelids are stuck together by a crusty glue-like substance.

Sound familiar?

Sleep crust, also called eye gunk or by its technical name, rheum, is pretty common. This mixture of mucus, tears, and skin cells is something that naturally occurs while you’re snoozing.

There’s definitely a spectrum of normal, everyday eye gunk and sleep crust that signals something could be wrong. We’ll fill you in on what this stuff is, why it appears on your eyelids in the morning, and how to take care of it.

First of all, what do we mean by crusty eyes? Crusty eyes in the morning can include any of the following symptoms:

  • white, cream-colored, or light yellow crust gathered in the corners of your eyelids when you wake up
  • eyelashes that are stuck to each other with watery or solid discharge from your eyes
  • irritation, redness, and a filmy layer around your eyes when you first open them

Keep reading to find out what’s normal when it comes to eye crust and when you should you be concerned.

Chances are, the sleep crust in your eyes is perfectly normal and part of your body’s amazing, self-regulating cleaning system.

Natural causes

During the day, blinking does the job of wiping away dust, old cells, extra mucus, and tears from your eyes. While you’re sleeping, you aren’t blinking, but these waste products are still being washed out of your eyes.

Some nights (and for some people, it’s most nights), there might be enough to create a crusty film on the corner of your eyelids. If you have allergies, you may notice extra eye crust during certain times of year. This still falls within the realm of a natural cause.


Blepharitis is the technical term for eyelid inflammation. Blepharitis has several possible causes, but one of the symptoms can be extra crusty discharge from your eyes during the night.

Eye redness or irritation, eyelids that stick together, or skin flakes at the base of your eyelid can indicate that you have blepharitis. Blepharitis typically only affects one eye at a time.


Conjunctivitis (pink eye) is any kind of inflammation that impacts your conjunctiva, which is a thin membrane that lines part of your eye.

Conjunctivitis can be bacterial or viral. It can also be related to allergies or environmental factors. When you have pink eye, you may notice extra crust gathering in the corner of your eye. It may cause a watery discharge to build up in your eye and create a gritty feeling between your eyelids.

Conjunctivitis can be in one eye, or it can affect both.

Eye stye

Sties are infected or inflamed oil glands or follicles in your eyelid. A stye can be painful, and it can also cause yellow mucus to build up in the corners of your eye.

If you have a stye, you’ll typically notice that only one of your eyes is getting extra crusty.

Blocked tear duct

A blocked tear duct stops your eyes from draining normally. If you have this condition, you may notice that small balls of yellow or white mucus are gathering around the corner of one of your eyes. Other symptoms include redness, irritation, pain, and swelling in your eyelid.

Dry eye

When you have chronic (or even occasional) dry eye, your eye may produce stringy mucus. This can result in an accumulation of eye crust that’s gritty or sticky.

If eye crust is your only symptom, you can probably treat it at home.

The American Academy of Ophthalmology puts emphasis on washing your hands before you try to rub any morning goop out of your eyes. It’s hard to resist the impulse to simply wipe crust from your eyes, but your hands often carry bacteria and germs.

Instead of using your bare (dirty) hands, try a clean washcloth with warm water on it. Apply the washcloth to your eyes gently, and most eye crust will dissolve on its own. You might need to have some patience and leave the washcloth on for a few minutes to completely clear your eye.

If your eyes feel gritty or dry after wiping out the crust, you may want to use eye drops to hydrate your eyeballs and get ready for the day. Hydrating eye drops or saline solution are available over-the-counter and can cleanse your eye of any remaining film or gunk.

Some symptoms indicate that it’s time to go beyond home remedies and see an eye doctor. These symptoms include:

  • any kind of pain in your eye
  • redness and irritation in your eye
  • difficulty opening your eye, due to eye gunk or otherwise
  • green or dark yellow eye discharge
  • light sensitivity
  • blurred vision

Your eye doctor will do an initial exam to determine the cause of your symptoms. If necessary, your doctor may prescribe prescription-strength eye drops or antibiotics to address any kind of infection or inflammation, such as blepharitis or conjunctivitis. Chronic dry eye may also be treated with eye drops.

If you take good care of your eyes, you may well find that there’s less eye gunk greeting you when you wake up in the morning. Here are some eyelid hygiene tips:

If you’re waking up with sleep crust in your eyes, it’s most likely the result of your eyes doing their perfectly natural and healthy daily cleansing ritual.

However, if you’re accumulating a lot of crust specifically in one eye, if you notice that your eye crust is a strange color, or if you have symptoms of itching or redness, there may be another health condition at play.

Your eyes are a highly complex and sensitive organ, so if you’re concerned about their health, speak with a doctor right away.