Rheum dries and gathers as a crust in the corners of the eyes or the mouth, on the eyelids, or under the nose. It is formed by a combination of mucus (in the case of the eyes, consisting of mucin discharged from the cornea or the conjunctiva), nasal mucus, blood cells, skin cells, or dust.

What causes crusty eyes in the morning?

When you’re sleeping, your eyes continue to manufacture tears and mucus. But since you’re not blinking, the excess matter gathers in the corners of your eyes and in your eyelashes, says ophthalmologist Aimee Haber, MD. “Morning crusting contains the oil, mucous and dead cells that your eye has produced overnight,” Dr.

Does everyone get rheum?

Everyone produces the mucus that causes eye boogers. This is normal in healthy eyes. However, some changes in lifestyle or eye health may cause the eyes to produce excess mucus. These changes can also make it more likely that the rheum sticks to the eyes.