A swollen eyelid is the inflammation or excess fluid (edema) in the connective tissues surrounding the eye. Swollen eyes may or may not be painful, and the condition can affect both the upper and lower eyelids.
Swelling of the eyelids can be a sign of a more serious, potentially sight-threatening health problem, such as orbital cellulitis, Graves' disease and ocular herpes.
It's important that you visit your eye doctor for a thorough eye exam if your symptoms persist, worsen or change.
Swelling of the eyelids is a symptom of an underlying cause, such as allergy or infection. Swollen eyes usually are accompanied by one or more of the following:
Eye irritation, such as an itchy or scratchy sensation
Sensitivity to light (photophobia)
Excess tear production, resulting in watering eyes
Obstructed vision (depending on the extent of the swelling)
Redness of the eyelid
Red eyes and inflammation of the conjunctiva
Eyelid dryness or flaking
Pain, particularly when swollen eyelids are caused by infection
Here is a closer look at some of the most common symptoms of swollen eyelids:
Your swollen eyelids may be the result of allergies. Most of the time, itchy eyes are caused by some type of allergy. An irritating substance — such as pollen, dust and animal dander — causes the release of compounds called histamines in the tissues around the eyes, which results in itching, redness and swelling.
Your eyelids may swell as a reaction to photophobia, or light sensitivity, which is an intolerance of light. Sources such as sunlight, fluorescent light and incandescent light all can cause discomfort, along with a need to squint or close your eyes. Headaches also may accompany light sensitivity.
Swollen eyelids can be caused by watery eyes. What causes the watery eyes? Chronic irritation from dry eye syndrome can result in an over-production of the watery component of tears, which is produced by glands located behind the upper eyelid (lacrimal glands).
Your swollen eyelids may be a result of redness in your eyes. Red or bloodshot eyes are very common and have many causes. Red eye usually is a symptom of other eye conditions that can range from benign to serious.
Eye discharge, or "sleep" in your eyes, could be causing the swelling of your eyelids. Eye discharge is a combination of mucus, oil, skin cells and other debris that accumulates in the corner of your eye while you sleep. It can be wet and sticky or dry and crusty, depending on how much of the liquid in the discharge has evaporated.
Dry eye syndrome can cause a range of issues, including swollen eyelids. Dry eye syndrome is caused by a chronic lack of sufficient lubrication and moisture on the surface of the eye. Consequences of dry eyes range from subtle but constant eye irritation to significant inflammation and even scarring of the front surface of the eye.
Eye pain is frequently accompanied by blurred vision, redness (bloodshot eyes), sensitivity to light and swollen eyelids. Eye pain is a catch-all phrase to describe discomfort on, in, behind or around the eye.
When to see an eye doctor
During the exam, your eye doctor will be able to determine the cause of your swollen eyelids and the most effective treatment.
Puffy vs. swollen eyes
The term "puffy eyes" often is used to describe swollen eyes, but the two conditions are different.
Swollen eyes are caused by an inflammatory response to allergy, infection or injury, whereas the term puffy eyes is better suited to describe soft and swollen eyelids that are due to water retention, lack of sleep or genetic traits like age-related sagging or puffiness of the eyelids (that typically affect both eyes).
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Page updated October 2020