Eye pain is a catch-all phrase to describe discomfort on, in, behind or around the eye.
The pain can be unilateral or bilateral — in other words, you can experience right eye pain, left eye pain, or the discomfort that affects both eyes. There’s no evidence that right eye pain occurs more frequently than left eye pain, or vice versa.
In some cases, such as an eye injury, the cause of eye pain is obvious. But often it’s difficult to know why your eye hurts.
To complicate matters, the severity of eye pain does not indicate how serious the underlying cause of the discomfort is. In other words, a relatively minor problem, such as a superficial corneal abrasion, can be very painful. But several very serious eye conditions — including cataracts, macular degeneration, the most common type of glaucoma, a detached retina, and diabetic eye disease — cause no eye pain whatsoever.
Eye pain symptoms include:
Eye pain also is frequently accompanied by blurred vision, redness (bloodshot eyes) and sensitivity to light.
Here are several common causes of eye pain affecting the front surface of the eye:
1. Corneal foreign body.
Not surprisingly, what often causes a foreign body sensation in the eye is an actual foreign body. Common foreign bodies that can adhere to and become embedded in the surface of the cornea include metal shavings, inorganic grit (sand, tiny stone particles), sawdust and other organic material.
The discomfort from a corneal foreign body can range from mild to severe, and typically it is most bothersome when you’re blinking (since the eyelid often is rubbing across it during blinks). Blurred vision and sensitivity to light also are common.
A corneal foreign body requires urgent attention from an eye doctor, because material embedded in the cornea can quickly cause a serious eye infection.
Most corneal foreign bodies can be removed easily in your eye doctor’s office. Antibacterial eye drops may be prescribed to prevent infection while the cornea heals.
2. Corneal abrasion.
This is a scratched cornea. Although most corneal abrasions are not serious, they can be very uncomfortable and also cause light sensitivity and watery eyes.
Many superficial corneal scratches heal on their own within 24 hours. But deeper abrasions can lead to a serious eye infection and even a corneal ulcer if left untreated.
Because it’s often impossible to tell if eye pain is due to a minor scratch, a deep abrasion or a corneal foreign body, it’s a good idea to see an eye doctor for any sharp discomfort of the eye that does not resolve very quickly, to determine the underlying cause.
3. Dry eyes.
Another very common cause of eye discomfort is dry eyes. Usually dry eye discomfort begins more slowly and gradually than eye pain from a corneal foreign body or abrasion. Sometimes dry eyes can lead to a corneal abrasion, because there are not enough tears on the surface of the eye to keep the cornea moist and slippery.
If using lubricating eye drops significantly improves comfort, the cause of the pain is probably dry eyes. In most cases, dry eye does not require urgent attention; but your eye doctor can perform tests to determine the severity of the dryness and recommend the most effective treatment.
Less common causes of anterior eye pain (pain on or “in” the eye) include:
A very serious cause of pain in the eye is a condition called endophthalmitis (en-dahf-thal-MITE-is), which is inflammation of the interior of the eye. It usually is caused by a bacterial infection from a penetrating eye injury or it can be a rare complication of cataract surgery or other eye surgery.
Endophthalmitis, in addition to causing eye pain, causes redness, swollen eyelids and decreased vision. If you have these symptoms after cataract surgery or other eye surgery, see an eye doctor immediately.
Common causes of pain behind the eyes are migraine headaches and sinus infections.
In the case of a migraine headache, the pain almost always is behind only one eye and often is accompanied by pain elsewhere on the same side of the head.
Pain behind the eye from a sinus infection usually is less severe than pain from a migraine, and both eyes may be affected.
Though pain behind the eyes from these causes typically is not an emergency, if you have chronic or recurring pain of this type, see an eye doctor or general physician for treatment and to see what can be done to prevent future episodes.
One of the most common causes of pain around the eyes is a stye (hordeolum) in the eyelid.
A stye doesn’t require urgent attention from an eye doctor and usually can be successfully treated at home by applying warm compresses to the eyelid several times a day for a few days.
Blepharitis is another common problem that can cause swollen eyelids and discomfort around the eyes.
Computer vision syndrome (also called digital eye strain) also can cause pain around the eyes. This is not an urgent problem, and there are simple steps you can take to relieve computer eye strain.
A much less common and much more serious cause of pain around the eyes is a condition called optic neuropathy, which can cause permanent vision loss. Accompanying symptoms are usually decreased visual acuity and reduced color vision, and the pain typically is worse with eye movements.
Eye pain that may be caused by optic neuropathy requires immediate attention by an ophthalmologist and a neurologist. Among people under 40, multiple sclerosis and other neurological conditions are the most common causes of optic neuritis.
You should consider any eye pain an emergency. Almost always, the right eye pain treatment is to immediately schedule an eye exam with an eye doctor near you. Only an eye care professional can determine the exact cause of your eye pain and prescribe the correct treatment to prevent damage to the eye and possibly permanent vision loss.
In particular, see your eye doctor immediately if you have a painful eye and:
The pain occurred immediately after grinding metal, sawing wood, or other activities that might cause a foreign body injury (especially if you were not wearing safety glasses or protective eyewear).
The pain is severe, came on suddenly, and you have a history of glaucoma. This could signal an acute attack of a less common form of glaucoma called angle-closure glaucoma, which can cause rapid vision loss and is a medical emergency.
When it comes to eye pain, don’t take chances — see an eye doctor as soon as possible to determine the exact cause of the pain and receive the right eye pain treatment.