Eye stones are small, yellowish-white deposits that form on the inside of your eyelids. Medically called conjunctival concretions, they’re surprisingly common, showing up in about 40% of patients in one study of 500 people. Most are tiny and cause no symptoms at all, but when they grow large enough to poke through the surface of the inner eyelid, they can scratch your eye with every blink.
What Eye Stones Actually Are
Conjunctival concretions are small clusters of protein, mucus, and cellular debris that collect just beneath the thin tissue lining the inside of your eyelids. They sit in the palpebral conjunctiva (the pink tissue you see when you pull your lower lid down) or in the curved pockets where the eyelid meets the eyeball. Despite the name “stones,” they don’t contain the organized calcium crystal structures you’d find in kidney stones. The older medical term “lithiasis” (meaning stone formation) turned out to be misleading once researchers examined them under electron microscopy and found no definitive calcium crystal pattern.
They tend to appear as one or several small dots, sometimes barely visible without magnification. An eye doctor can spot them easily during a routine exam using a slit lamp, the specialized microscope used in eye exams. Many people have them without ever knowing.
What Causes Them
Eye stones form when debris accumulates in the tissue of the inner eyelid. Chronic inflammation plays a central role. Conditions like long-term dry eye, allergies, and blepharitis (eyelid inflammation) create an environment where mucus, dead cells, and proteins build up and solidify over time. Aging is another major factor. In the prevalence study of 500 patients, deposits appeared in people as young as 20, but the highest rates occurred between ages 30 and 80.
Anything that increases chronic irritation of the eye surface can raise your risk. Long-term contact lens wear, environmental dust or pollution exposure, and frequent eye rubbing all contribute. The underlying process is straightforward: irritated eyelid tissue produces more mucus and sheds more cells, and that material gradually compacts into small, firm deposits.
What They Feel Like
Small concretions buried beneath the eyelid surface cause no symptoms whatsoever. This is the most common scenario, which is why so many people have them without realizing it. Problems start when a concretion grows large enough to break through the conjunctival surface and become exposed. At that point, the hard deposit rubs directly against your cornea (the clear front surface of your eye) every time you blink.
The sensation is often described as feeling like something is stuck in your eye, a persistent grittiness or scratching that doesn’t go away with blinking or rinsing. It’s typically worse with blinking rather than better, which distinguishes it from a loose eyelash or piece of dust. Some people notice increased tearing or redness on the affected side. If the exposed stone repeatedly scratches the cornea, it can cause a corneal abrasion, which brings sharper pain, light sensitivity, and blurred vision. Left untreated, corneal abrasions carry a risk of infection and, in rare cases, permanent scarring.
How They’re Removed
If your eye stones aren’t causing symptoms, they don’t need treatment. Many eye doctors notice them during routine exams and simply note them in your chart. Treatment only becomes necessary when a concretion erodes through the surface and starts irritating your eye.
Removal is a quick, straightforward office procedure. Your eye doctor applies numbing drops to the eye, flips the eyelid, and uses a fine needle or small instrument to lift the deposit out of the tissue. The whole process takes minutes and the relief is usually immediate. Some mild irritation or a scratchy feeling can linger for a day or two afterward as the tiny spot where the stone sat heals over.
Concretions can recur, especially if you have ongoing eyelid inflammation or dry eye. Managing the underlying condition, whether through lubricating drops for dryness, allergy treatment, or lid hygiene for blepharitis, helps reduce the likelihood of new deposits forming.
Eye Stones vs. Tear Duct Stones
The term “eye stones” sometimes also refers to dacryoliths, which are a different condition. While conjunctival concretions sit on the inner eyelid surface, dacryoliths form inside the tear drainage system, the tiny channels and sac that drain tears from your eye into your nose.
Dacryoliths develop when tear flow slows or stagnates, allowing debris and proteins to accumulate around a core particle. Studies of 86 dacryolith samples found they were composed almost entirely of organic material, roughly 20% amino acids, with proteins and mucoproteins making up the bulk. Interestingly, researchers found fibers in the cores of some stones that appeared to come from cotton swabs used in cosmetics, suggesting that foreign material entering the tear system can serve as a seed for stone formation. Trace amounts of silicon, magnesium, calcium, iron, and even titanium and bismuth were found as inorganic inclusions, but none of the stones were the “hard” calcium phosphate type.
Dacryoliths cause different symptoms than concretions. Instead of a scratching sensation, they block tear drainage, leading to persistent watery eyes (epiphora), discharge from the tear duct opening, and sometimes infection of the tear sac or the small channels leading to it. These infections are frequently misdiagnosed as chronic conjunctivitis or styes before the true cause is identified. Treatment typically involves a surgical procedure to open the blocked channel and remove the stone.
Preventing Recurrence
You can’t completely prevent eye stones, but you can reduce the conditions that encourage them. Keeping your eyelids clean with warm compresses and gentle lid scrubs reduces the debris and inflammation that feed concretion formation. If you have chronic dry eye, consistent use of preservative-free artificial tears helps maintain a healthier ocular surface. Treating allergies aggressively during peak seasons limits the chronic inflammatory cycle. If you wear contact lenses, following proper hygiene and replacement schedules minimizes the extra irritation that contributes to deposits over time.