A person may experience swelling in one or both eyelids. Swelling may be painless or accompanied by itching or pain. Eyelid swelling is distinct from bulging eyes Eyes, Bulging Bulging or protruding of one or both eyes is called proptosis or exophthalmos. Exophthalmos is usually used when describing bulging eyes caused by Graves disease, a disorder causing overactivity... read more 
, although a few disorders can cause both.
Causes
Eyelid swelling has many causes (see table Some Causes and Features of Eyelid Swelling Some Causes and Features of Eyelid Swelling 
). It usually results from an eyelid disorder but may result from disorders in and around the eye socket (orbit) or from disorders elsewhere in the body that cause widespread swelling.
Common causes
The most common causes of eyelid swelling are allergic, including
Local allergy (contact sensitivity)
More widespread allergic reaction (for example, angioedema Angioedema Angioedema is swelling of areas of tissue under the skin, sometimes affecting the face and throat. Angioedema can be a reaction to a drug or other substance (trigger), a hereditary disorder... read more
or allergic rhinitis Rhinitis Rhinitis is inflammation and swelling of the mucous membrane of the nose, characterized by a runny nose and stuffiness and usually caused by the common cold or a seasonal allergy. Colds and... read more 
)
Swelling of one place in one eyelid is common and is most often caused by a blocked oil gland (chalazion Chalazion and Stye (Hordeolum) Chalazia are enlargements of an oil gland (similar to a pimple) deep in the eyelid caused by an obstruction of the gland’s opening. Styes are usually infected eyelash follicles. A chalazion... read more 
) or a bacterial infection of a hair follicle (stye Chalazion and Stye (Hordeolum) Chalazia are enlargements of an oil gland (similar to a pimple) deep in the eyelid caused by an obstruction of the gland’s opening. Styes are usually infected eyelash follicles. A chalazion... read more or hordeolum Chalazion and Stye (Hordeolum) Chalazia are enlargements of an oil gland (similar to a pimple) deep in the eyelid caused by an obstruction of the gland’s opening. Styes are usually infected eyelash follicles. A chalazion... read more ).
Less common causes
Less common causes of eyelid swelling include
Disorders that cause generalized body swelling, particularly a type of kidney disease called nephrotic syndrome Nephrotic Syndrome Nephrotic syndrome is a disorder of the glomeruli (clusters of microscopic blood vessels in the kidneys that have small pores through which blood is filtered) in which excessive amounts of protein... read more
Bacterial infection of the skin of the eyelids and around the eyes (preseptal Preseptal Cellulitis Preseptal cellulitis is infection of the eyelid and of the skin and tissues around the front of the eye. (See also Introduction to Eye Socket Disorders.) Both preseptal cellulitis and orbital... read more
or periorbital cellulitis Preseptal Cellulitis Preseptal cellulitis is infection of the eyelid and of the skin and tissues around the front of the eye. (See also Introduction to Eye Socket Disorders.) Both preseptal cellulitis and orbital... read more )Overactive thyroid (hyperthyroidism Causes
)
An overactive thyroid gland can cause bulging eyeballs but does not cause swollen eyelids.
Rare but dangerous causes of eyelid swelling are infection within the orbit and around and behind the eye (orbital cellulitis Orbital Cellulitis Orbital cellulitis is infection affecting the tissue within the orbit and around and behind the eye. Infection can spread to the orbit from sources such as the sinuses around the nose. Symptoms... read more 
) and blockage of a vein at the base of the brain by an infected blood clot (cavernous sinus thrombosis Cavernous Sinus Thrombosis Cavernous sinus thrombosis is a very rare disorder in which a blood clot (thrombosis) forms in the cavernous sinus (a large vein at the base of the skull). Cavernous sinus thrombosis is usually... read more ).
Evaluation
The following information can help people decide whether a doctor's evaluation is needed and help them know what to expect during the evaluation.
Warning signs
In people with eyelid swelling, certain symptoms and characteristics are cause for concern. They include
Fever
When to see a doctor
People with warning signs should see a doctor right away. If pain occurs, people usually want to see a doctor within a day or two so that they can start to feel better.
What the doctor does
Doctors first ask questions about the person's symptoms and medical history. Doctors then do a physical examination. What they find during the history and physical examination often suggests a cause of the eyelid swelling and the tests that may need to be done (see table Some Causes and Features of Eyelid Swelling Some Causes and Features of Eyelid Swelling ).
Doctors ask
How long the swelling has been present
Whether swelling affects the upper and/or lower eyelids in one or both eyes
Whether any injury (including insect bites) or eye surgery has occurred
Whether itching, pain, headache, changes in vision, fever, or eye discharge is present
Whether symptoms affecting other areas of the body are also occurring
Whether the person has disorders (for example, heart, kidney, or liver disease) or is taking drugs (for example, angiotensin-converting enzyme inhibitors) that are known to cause swelling or has changes in tolerance of cold or heat that might indicate a thyroid disorder
Whether the person is using any drugs in or around the eye
Whether there have been any changes in over-the-counter products used on the face or around the eye (for example, new makeup, face creams, or cleansers or new detergent to launder bed linens or towels)
During the physical examination, doctors look for signs of disorders that may affect other parts of the body, but the focus is primarily on the eyes. They look for runny nose and other signs of allergies, toothache or headache, which may indicate a dental or sinus infection, fever, and changes in skin near the eye.
Any eyelid or eye sore is evaluated by using a slit lamp What Is a Slit Lamp? 
(an instrument that enables a doctor to examine the eye under high magnification). Doctors check the location and color of the swelling and whether the eyelid is tender or warm, whether vision is affected, whether eye muscles are functioning normally, and whether any discharge is present.
Testing
In most cases, doctors can determine the cause of eyelid swelling based on the symptoms and the findings during the physical examination, and no testing is needed. However, if doctors suspect orbital cellulitis Orbital Cellulitis Orbital cellulitis is infection affecting the tissue within the orbit and around and behind the eye. Infection can spread to the orbit from sources such as the sinuses around the nose. Symptoms... read more or cavernous sinus thrombosis Cavernous Sinus Thrombosis Cavernous sinus thrombosis is a very rare disorder in which a blood clot (thrombosis) forms in the cavernous sinus (a large vein at the base of the skull). Cavernous sinus thrombosis is usually... read more , they immediately do computed tomography (CT) or magnetic resonance imaging (MRI). If a heart, liver, kidney, or thyroid disorder is suspected, doctors do laboratory tests and sometimes various imaging tests.
Treatment
The best way to treat eyelid swelling is to treat the disorder that is causing the swelling. There is no specific treatment for the swelling.
Key Points
Eyelid swelling Eyelid Swelling A person may experience swelling in one or both eyelids. Swelling may be painless or accompanied by itching or pain. Eyelid swelling is distinct from bulging eyes, although a few disorders can... read more may be caused by a disorder of the eye or eyelid or by a disorder elsewhere in the body.
People with sudden double vision Vision, Double Double vision is seeing two images of one object. Double vision may occur when only one eye is open (monocular diplopia) or, more commonly, when both eyes are open (binocular diplopia). Binocular... read more or loss of vision Vision Loss, Sudden Loss of vision is considered sudden if it develops within a few minutes to a couple of days. It may affect one or both eyes and all or part of a field of vision. Loss of only a small part of... read more should see a doctor immediately.
People with fever or a bulging eye Eyes, Bulging Bulging or protruding of one or both eyes is called proptosis or exophthalmos. Exophthalmos is usually used when describing bulging eyes caused by Graves disease, a disorder causing overactivity... read more
should see a doctor within hours if possible.
