Most people wake up to that yellowish crust in the corner of their eyes — it’s totally normal. Here’s what it actually is and when to be concerned:
💤 What Is It?
That morning gunk is called rheum (medical term) — a mix of mucin (mucus), oils, skin cells, dust, and tear residue
Blinking during the day washes it away, but at night, with no blinking, it accumulates and dries until you wake up
Why Yellow or Crusty?
- Yellow/cream-colored rheum results from the mix of mucus, oils, and dead cells
- Sometimes you may see stringy, white mucus if you have dry eye or allergies
When Is It Normal?
- A bit of overnight crust is healthy — it shows your eyes are self-cleaning .
- Allergies or dry eyes can increase the amount — still common but worth monitoring .
When to See a Doctor
See a healthcare provider if you have these along with a lot of crust:
- Yellow-green or gray discharge
- Crusting causing eyelids to stick shut
- Redness, pain, blurred vision
- Light sensitivity or swelling
These may indicate bacterial/viral conjunctivitis, stye, blepharitis, blocked tear ducts, or dry eye disease
How to Clean Your Eyes
- Wash your hands
- Use a warm, damp washcloth to gently wipe away crust
- Practice good eyelid hygiene — remove makeup, cleanse lids before bed
Avoid using fingers or picking, which can transfer bacteria
✅ In a Nutshell:
That crusty yellow sleep is harmless rheum — a natural combination of mucus, oil, and debris. Clean gently each morning. If it’s excessive, discolored, or causing symptoms like redness or pain, book an eye exam.
Let me know if you’d like details on dry eye relief, allergy-related eye care, or tips for preventing morning crust!