Chalazion: What It Is, What It Looks Like, and How It Differs from a Stye

You notice a firm, round pea-sized lump on your eyelid—and your first thought is usually: a stye. A chalazion looks similar but behaves differently: it is almost painless and does not go away within a week. I explain step by step what this formation is, where it comes from, and how not to confuse it with a stye.

What a chalazion is and why it is called a cold stye

A chalazion is a small lump within the thickness of the eyelid that appears due to blockage of an oil gland duct. Meibomian glands lie in the eyelid just behind the eyelashes; there are more than 150 in one eyelid, and they secrete a thin oily substance that protects the tear film from drying out. The duct becomes blocked—the secretion remains inside, and a nodule forms around it.

A chalazion is called chronic inflammation, unlike an acute stye, which is why in everyday speech it is sometimes called a "cold stye." A stye is caused by bacteria; it is an acute inflammation of the gland, whereas a chalazion is chronic and non-infectious inflammation, and in appearance it is closer to a benign formation. It is not dangerous to life, but it causes discomfort: a large lump presses on the eyeball, which causes astigmatism and makes the image partially blurry.

What a chalazion looks like on the upper and lower eyelid

For the first two days the lump behaves like a stye: the eyelid is irritated, swollen, and there is moderate pain. Then the swelling subsides, and a round, painless swelling remains on the eyelid. It grows slowly, usually over about a week. At this point a red or gray spot is visible on the inner surface of the eyelid.

What this looks like in practice: a firm formation about the size of a small grain can be felt, the skin over it is raised and mobile, and on the conjunctival side there is an area of redness with a grayish center. If the chalazion grows to about 5 mm or more, it may become painful. A chalazion can appear on both the upper and lower eyelid.

Causes of chalazion in adults and children

The mechanism is the same—blockage of the duct of a meibomian gland or a gland of Zeis. The plug itself does not always cause a chalazion: more often it ruptures spontaneously and nothing forms. A chalazion often appears against the background of blepharitis—inflammation of the eyelid skin. Other circumstances include: a previous stye, exposure to cold and colds, reduced immune defenses, wearing contact lenses, and naturally oily skin. The exact reasons why in one person the plug resolves and in another it turns into a nodule are unknown.

Age does not matter: chalazion occurs in people of all age groups, including children, and most often in adults aged 30–50.

How a chalazion differs from a stye

• Pain: a stye hurts from the first day; a chalazion hurts only during the first 1–2 days, after which the pain goes away.
• Appearance: a stye is an acute inflammation of the gland and may be filled with pus; a chalazion is a firm, painless swelling that grows slowly.
• Nature: a stye is caused by infection; a chalazion is non-infectious.
• Rule of thumb: a hard and not very painful lump is more likely a chalazion than a stye.

How a doctor identifies a chalazion

The diagnosis is made based on the clinical picture: an examination of the eyelid is sufficient. Additional tests are rarely needed. The reason is that a malignant skin tumor of the eyelid sometimes resembles a chalazion—if the doctor suspects this, a biopsy is ordered. In recurrent chalazion, the cause is sought: possible causes include skin diseases and, in rare cases, a malignant tumor.

When a lump on the eyelid requires a visit to an ophthalmologist

You should come for an appointment if the lump continues to enlarge or an area of eyelash loss appears. Suppuration is a separate reason: pain and redness of the eyelid skin develop, and spontaneous rupture with discharge of pus from the conjunctival side is possible. Frequent recurrences are also a reason for examination.

An urgent ophthalmologist examination is needed if the eyelid has become sharply and severely swollen and painful, pain and swelling are rapidly increasing, pus is coming from the eye or eyelid, the infection has spread to the eye or eyelid, or vision has worsened. With such signs, it is better not to postpone the visit and to see an ophthalmologist the same day.

A quick self-check: in good light, in front of a mirror, see whether the skin over the lump moves, whether it hurts when lightly touched, whether there is a red or gray spot on the inner side of the eyelid, and whether the eyelashes nearby are thinning. This is not a diagnosis—just a way to gather questions for the doctor.

A chalazion by itself is not a reason to call an ambulance. 103 or 112—if there is a threat to life: for example, severe eye trauma or a sudden sharp deterioration of the condition.

This material is for reference: it helps you understand what is happening with the eyelid, but does not replace a doctor's consultation—the final answer is given by an ophthalmologist during an examination.

This content is for reference and does not replace a doctor's consultation. Medical disclaimer