Overview
A thin film of tears covers the front of the eye and is spread across it by every blink. It has a watery layer, an oily layer that slows evaporation, and mucus that helps it stick. Dry eye happens when too little tear fluid is made, when the film evaporates too quickly, or when the tears are of poor quality.
The result is a surface that is not kept smooth, so it feels rough and the vision that depends on it becomes unsteady. Dry eye is very common, it often comes and goes, and it usually responds well to simple measures.
Symptoms
- A scratchy or gritty feeling, as though something is in the eye
- Stinging or burning
- Redness and soreness
- Eyes that water more than usual
- Blurred vision that clears for a moment after blinking
- Discomfort in bright light
- Tired, heavy eyes at the end of the day
- Difficulty wearing contact lenses
When to see a doctor
See a doctor or optician within a few days if the eye is red and you wear contact lenses, if there is a discharge of pus or mucus, if the eyelids have changed shape, or if symptoms are no better after a few weeks of drops and self care.
Causes
Often no single cause is found. Tear production falls naturally with age, and the small glands in the eyelids that make the oily layer can become blocked, so tears evaporate too quickly.
Air conditioning, fans, wind, smoke, dust and long hours on a screen all dry the surface. Some medicines, including certain tablets for allergy, colds, and depression, reduce tear production. Dry eye can also be part of a wider condition such as Sjogren syndrome, or follow eye surgery.
Risk factors
- Being over 50
- Being a woman, particularly around and after the menopause
- Wearing contact lenses
- Long hours at a screen
- Air conditioned, heated, smoky, windy or dusty surroundings
- Smoking and drinking a lot of alcohol
- Some medicines for allergy, colds, and mood
- Blepharitis, an inflammation of the eyelid margins
- Autoimmune conditions such as Sjogren syndrome and lupus
- Previous eye surgery
Complications
For most people dry eye stays a discomfort. Severe dry eye that is not treated can damage the cornea, the clear front window of the eye, and a damaged surface is more open to infection.
Long standing symptoms also make reading, driving at night and screen work tiring, and can make contact lenses impossible to wear.
Prevention
- Taking regular breaks from screens and setting the monitor a little below eye level
- Blinking fully and deliberately during close work
- Cleaning the eyelids daily with warm water and a gentle massage
- Using a humidifier in dry or air conditioned rooms
- Keeping out of the direct blast of fans, coolers and car vents
- Wearing wraparound sunglasses in wind and dust
- Not smoking, and limiting alcohol
- Wearing spectacles instead of contact lenses when the eyes feel dry
Diagnosis
The diagnosis rests mainly on the symptoms and an examination of the eye with a magnifying light, looking at the tear film, the lid margins and the surface of the eye.
Simple tests may be used: a dye that shows up dry or damaged patches on the surface, a measure of how long the tear film lasts before it breaks up, and a small paper strip placed under the lid to measure how much tear fluid is produced. Blood tests are done only when an autoimmune cause is suspected.
Treatment
Treatment starts with the measures listed under prevention, together with lubricating drops, commonly called artificial tears, which are available from a pharmacy. Thicker gels and ointments last longer and are often used at night. Drops without preservative are usually preferred when they are needed many times a day.
If the lid glands are blocked, warm compresses, gentle lid massage and lid cleaning are the mainstay, and a doctor may add a course of drops or tablets to settle the inflammation.
When drops are not enough, an eye doctor may prescribe medicated drops that reduce inflammation on the surface, or place tiny plugs in the tear drainage openings so that the eye keeps its own tears for longer. Surgery on the eyelids is used only rarely. Where another condition or a medicine is responsible, treating or reviewing that is part of the plan, and prescribed medicines should not be stopped without asking the doctor.
Myths and facts
Things people often say about this. Open each one to see what is true.
Myth“My eyes water all day, so they cannot possibly be dry.”What is true?
Fact
Watery eyes are one of the common symptoms of dry eye. When the surface becomes dry and irritated, the eye responds with a flood of watery tears that run down the cheek instead of coating the eye properly, so the discomfort carries on.
Myth“Dry eye only happens to old people.”What is true?
Fact
Risk does rise after about the age of 50 and it is more common in women, but long hours on screens, contact lenses, smoky or dusty air, air conditioning, some medicines and conditions such as Sjogren syndrome make it common in younger people too.
Myth“It is just a small nuisance, so there is nothing to treat.”What is true?
Fact
Most dry eye is indeed a nuisance rather than a danger. But severe dry eye that is left untreated can damage the cornea, the clear window at the front of the eye, so symptoms that keep going despite self care are worth showing to a doctor.
Myth“Screens have ruined my eyes and there is nothing to be done short of giving them up.”What is true?
Fact
Screens can make dry eye worse, but they do not have to be abandoned. Regular breaks away from the screen, keeping the monitor a little below eye level, blinking deliberately, adding moisture to dry indoor air, and staying out of direct wind, smoke and air conditioning all reduce symptoms.
Questions to ask your doctor
Tick the ones you want answered and take them with you.
Common questions
Can I use lubricating drops every day, for a long time?
Lubricating drops simply add moisture to the surface of the eye and are the usual first step in treatment. If they are needed very often, drops without preservative are generally preferred, and it is worth seeing a doctor to look for the underlying cause rather than continuing indefinitely on your own.
Will drinking more water cure my dry eyes?
Staying well hydrated is sensible and is part of general advice for dry eye, but on its own it rarely settles the symptoms. Most people also need lubricating drops and changes to their surroundings and screen habits.
Is dry eye a sign of something more serious?
Usually not. Occasionally it is one feature of an autoimmune condition such as Sjogren syndrome, particularly when there is also a very dry mouth or aching joints. Tell your doctor if those symptoms are present so the right tests can be arranged.
How long does it take to feel better?
Lubricating drops often ease the grittiness within minutes, but the surface takes longer to settle. Give the daily routine of lid care, breaks and drops several weeks before judging it, and see a doctor if there has been no change by then.
