What causes crusty eyes?

What causes crusty eyes, and how do we as mere humans break this ancient curse? If you have eyes yourself, you've woken up at some point with them filled with little crunchy ninja stars that hurt when you rub them. As a species, we've got to get to the bottom of this and find a way to deal with the crusty eye thing.

Understanding crusty eyes

Definitions and characteristics

We've all been there. You wake up, the day is full of yet-unrealized possibilities, and wham — crusty eyes in the mirror. This crust is the gunk left over after the water evaporates out of tears, and it's a lovely biological mess of proteins, captured airborne particles, and the unconfessed sins of leprechauns. You'll feel this as gunk sticking your eyelashes together or scummy goop in the corners of your eyes. Sometimes, just for fun, it dries to the point where it's basically sharp little crystals pressing on arguably the most vulnerable tissue you have (above the waist, at least).

Occurrence and triggers

This squalid condition is caused when your normally well-behaved tears stop draining through the tear ducts in the inside corners of your eyes and start piling up on the surface of the eyes. This is especially likely to happen while you're asleep. This is partly because eye crusties know enough to sneak in while we're helpless and partly because you're not blinking tears away while you're asleep. Dry night air can make the issue worse, as can allergies and infections.

Common causes of crusty eyes

Like any good plague, crusty eyes can have mysterious causes. Science nerds have been working on this, however, and they have some ideas.

Sleep-related factors

If your eyes are watering while you sleep, like if you sometimes sleep with your eyes partly open or you're kind-of waking up during the night, you might be overproducing tears. Over the 6-to-8 hours you're sleeping (10-12 for writers), the water from these tears can evaporate and leave you with the ocular crunchies.

Allergies and irritants

We tear up when we've got allergies, and there's nothing like a good puff of pollen or dust to get the eyes all shimmery. If you've got a lot of airborne particulates in your home, especially in the place where you sleep, you're asking for the crusty eye fairy to visit. Definitely rule out allergies with a decent air filter and maybe some allergy drops

Eye infections

Eye infections are definitely not nice, but at least if this is what's causing the crusty eye thing, you've got peace of mind because it won't last forever. Our eyes respond to germs the same way pirate ships respond to cannonballs; they take on water. This is kind of effective at flushing infectious junk out of your eyes, but it also feeds raw material into the eye crust factory and can really make a mess. As a fun bonus, if you have pink eye, your crusty eyes are really, really contagious, so you're definitely going to want to get an eye exam and maybe some drops, sterile gloves, bottles of cleanser and hand sanitizer, maybe a flamethrower, and high-quality stationery for those apology letters when all your friends get the infection from touching your house keys.

Managing and preventing crusty eyes

Okay, so how are we going to finally conquer crusty eyes once and for all? Basically, just by being clean, it turns out. You can dab your eyes with a damp cloth at night to clear away junk before you sleep. Keep your eyes hydrated with drops. Manage the dust and allergens in your home. Move to a remote space colony if you get pink eye. The usual.

Addressing crusty eye issues

Like love, death, and war, crusty eyes are a near-universal human experience. Unlike those more dignified issues, they're gross and kind of embarrassing to deal with. Crusty eyes have lots of causes, from just-one-of-those-things to serious eye infection, but there are also lots of options for preventing and managing them. You know what's good to do when you have crusty eyes and don't feel like you can tell anybody because you like having friends? Schedule an appointment with a local eye care professional and get it all checked out.

FAQ

Can allergies be a year-round cause of crusty eyes, or is it usually seasonal?

Allergies are often seasonal, but if you're allergic to everything the way some eye blog authors are, you're getting crusty eyes from Easter to Christmas, bro.

Are crusty eyes in the morning a sign of an eye infection?

Crusty eyes can be a sign of infection. It's not as dignified as fever or swollen glands, but it does happen. 

When is it necessary to consult an eye doctor for crusty eye issues?

Crusty eye issues become something to bring to the doctor when the problem is driving you nuts and you need a smart person to brainstorm solutions with. It's also good to check in if you think you have an infection or you've been self-diagnosing on WebMD again and need reassurance it's not a brain tumor.