Dry eye (keratitis sicca) is one of the most common causes of red eyes. Poor tear production results in dry eyes that feel scratchy and gritty. They may also burn, or feel like a foreign object is in the eye. Severe dryness may even trigger watery eyes if the surface of the cornea (the transparent front part of the eye) is irritated.
Although dry eyes can occur on their own, they can also signal another disease. Thyroid problems, arthritis and hormone disturbances such as menopause may contribute to dry eye symptoms. Such diseases may be diagnosed years after the first symptom of dry eyes appears.
Some medications can cause dryness of the eye. These include antihistamines like Reactine™ for allergies, antidepressants like Paxil™ and pills for heartburn like Losec™. Antibiotics such as tetracycline (used for acne) and some painkillers including Tylenol™ with codeine can also cause eye dryness.
Reduced tear production or a poor film of tears can be a significant problem in dry climates. In places like Western Canada, low humidity during the six to eight winter months can make dry eyes worse.
You can reduce eye dryness in several ways. First, try to avoid car heaters and any type of artificial ventilation, especially air conditioning, since it evaporates the tear film and makes eyes drier. Caffeinated products such as coffee, tea, pop and chocolate bars also dry out the eyes. Caffeine is in fact a diuretic, using fluid in the body to increase urine production.
Artificial tears can help lubricate the eyes. Drops such as Tears Naturale™ can be used during the day. A thicker drop in gel form, such as Refresh Liquigel™, works well at night. Severe dryness may require the use of lubricating ointments at bedtime.
Wrap-around sunglasses can keep wind and air from car vents off the face, reducing evaporation of the tear film. Simply drinking four to five glasses of water each day also improves tear production.
|Keratitis Sicca (dry eye)||Allergic Conjunc
|Redness||Mild redness spread out||Mild uniform redness||Obvious uniform redness|
Blurry, better after blinking
|Treatment||Lubricants like Tears Naturale™, Tear Gel™, Lacri-Lube™ ointment||Topical antihistamines||Topical antibiotics|
|Pain*||Yes, can be severe||Medium soreness||No, but eyeball is tender to touch|
|Redness||Redness around or on edge of cornea||Redness around or on edge of cornea||Redness of deeper blood vessels|
|Blurred Vision||Yes, if central corneal lesion||Hazy vision||No|
|Treatment||Topical antibiotics||Topical cortisone||Topical cortisone|
|*If you have eye pain call your doctor, especially if you wear contacts.|
The conjunctiva is the thin filmy membrane that covers the sclera (the white part of the eye) and lines the inside of the eyelids. Red itchy eyes, a stringy mucous discharge, and light sensitivity are all symptoms of allergic conjunctivitis. Other allergic conditions include asthma, eczema, allergic rhinitis and allergic sinusitis. Itchy eyes, a stuffy nose and a post-nasal drip are sure signs of an allergy to something.
Antihistamine eye drops are now available as an effective treatment for itchy eyes. Some of the new allergy drops only need to be used once or twice a day.
If eyelids swell with allergies, using a cold, dry compress made by wrapping a tea towel around a cold pack may help. Elevating the head with an extra pillow at night will also reduce eyelid swelling along with nasal and sinus congestion.
Those with allergies tend to be sensitive to light, and will appreciate toning down brightness. Wear sunglasses or regular glasses with a light to medium tint. Cutting down glare should also reduce visual discomfort and the urge to squint.
If your eyes itch as part of an allergic reaction, don’t rub them. This produces more histamine, which causes eye symptoms in the first place. Use a cold dry compress instead.
Oral antihistamines also help relieve itchy eyes. If symptoms persist or worsen over time, consider skin testing for allergies. A visit to the allergist may mean better treatment, since the specific allergen (cause of the allergy) may be identified.
Common causes of allergic conjunctivitis include cosmetics, dust, smoke, and airborne allergens like tree and flower pollen. Fortunately some allergies are seasonal and may vary from year to year.
If the conjunctiva becomes infected, eyes can become red. There is always discharge. The pus can leave the eyelids crusty and sticky, especially in the morning.
Many viruses and bacteria that cause infective conjunctivitis result from an upper respiratory tract infection. People often go to their family doctor with red eyes and discharge, while complaining of a cold and other symptoms. In this case, the family doctor may do a throat swab to check for certain bugs.
If you are experiencing unexplained eye redness or pain, contact your doctor or ophthalmologist.
Most conjunctivitis caused by a virus will gradually subside over a few days. Keeping the eyelids clean with Q-tips and warm water may be all the treatment that is needed.
If the cause is bacterial, topical eye antibiotics, drops or ointment prescribed by a physician should be used for at least five to seven days. If the conjunctivitis keeps returning, the eye may be swabbed for a sample. A culture study then grows the bugs to identify the source of infection.
If only one eye is red, it may mean an ulcer of the cornea. Bacteria and viruses are responsible for these ulcers, which cause pain and sensitivity to light. If the ulcer involves the central part of the cornea, vision may be blurred.
Corneal ulcers from any cause require urgent attention. An ophthalmologist must check them using a slit lamp biomicroscope to determine the cause and treatment. Scraping the cornea for a sample may be necessary. Examining scrapings under a microscope can help with diagnosis.
Remember that wearing contact lenses for too long or that fit poorly can cause a corneal abrasion (scrape) and ulcer. If you wear contacts and have a red eye, take them out and do not use them again until the eye is back to normal.
Topical antibiotic drops and ointment can be used for corneal ulcers caused by bacteria. An oral antibiotic may even be necessary. As well, the same herpes simplex virus that is responsible for cold sores may be causing the ulcer. In this case, topical drops usually do the trick.
Iritis is an inflammation of the iris, the coloured part of the eye. It inflames the front section of the eye. Iritis usually has medium soreness as opposed to severe pain, and can cause hazy vision. One risk is that inflammation in the front of the eye can cause adhesions (bands of scar tissue) and pupil irregularities.
Iritis requires urgent care. Usually, topical drops are used to dilate (open) the pupil and cortisone drops settle the inflammation.
Sometimes, iritis is associated with autoimmune conditions, including ulcerative colitis and lupus erythematosus. With autoimmune diseases, the immune or defence system mistakes its own body’s tissues for something foreign, and attacks them.
Think back to the conjunctiva, the thin membrane covering the sclera (the white part of the eye). The episclera is a layer of tissue between the conjunctiva and the sclera. It contains many blood vessels. In episcleritis, deeper blood vessels of the episclera are inflamed and the eyeball becomes tender to touch. There is no actual pain. As a general rule, vision is not affected. Episcleritis can also be related to autoimmune conditions, such as arthritis, and can happen repeatedly. Topical cortisone drops usually work.