What is Dry Eye Syndrome?
Dry eye occurs when there is a problem with the tears that normally keep the eye moist. Problems with the tear film include:
- the tears evaporate too quickly
- the eyes do not make enough tears
- the tears produced are of poor quality
It affects both eyes and most cases are mild to moderate.
Symptoms of Dry Eyes
- gritty, sandy, aching or burning eyes
- sensation of something in your eye
- persistent irritation
- intermittent blurred vision
- watery eyes
- contact lens intolerance especially towards the end of the day
- sensitivity to light
Why do my eyes water?
Some people are diagnosed with dry eyes even though they feel their eyes stream with tears. This may be because there is a problem with a different tear layer that irritates the surface of your eye. Your eye tries to deal with this by producing more watery tears to compensate for the underlying dryness, however this doesn’t help to correct the dryness in your eye.
Causes of Dry Eye Syndrome
- Ageing — dry eye commonly occurs as we age and affects more women than men.
- Increased evaporation of tears due to:
- Inflammation of the eyelids e.g. blepharitis is a very common cause
- Low humidity e.g. central heating, air conditioning or air travel
- Environmental factors e.g. windy conditions
- Low blink rate e.g. during reading, computer use, watching TV, driving
- Contact lens use
- Eyelid problems that stop the eyelids from closing completely e.g. Bells Palsy
- Eye surface changes — due to injury, infection or eye surgery e.g. laser correction for short sightedness.
- Systemic diseases — e.g. rheumatoid arthritis, Sjogrens, diabetes. See note below.
- Medications — dry eyes can be a side effect of medications e.g. anti-depressants, HRT, acne treatments. Do not stop or change your treatment unless agreed with your prescriber.
Treatment of Dry Eye Syndrome-making the most of your natural tears
There are simple changes you can make which may help reduce the evaporation of tears and symptoms of dry eye:
- Eyelid hygiene to control the blepharitis. See blepharitis page.
- Avoid very dry atmospheres — consider the use of a humidifier to moisten the air.
- Lower the temperature in a room slightly.
- Try not to rub your eyes.
- Wear goggles when swimming or working in a dusty atmosphere.
- If using a computer for long periods ensure that the monitor is at or below eye level, avoid staring at the screen and take frequent breaks to close/blink eyes.
- Limiting the use of contact lenses if these cause irritation.
- A diet rich in omega 3 fatty acids
Using artificial tears
- Artificial tears aim to supplement and replace your natural tears to make the eye more comfortable. They are not a cure.
- They do not contain any drugs which means they can be used as often as you need.
- If you have chronic dry eye it is important to use the drops even when your eyes feel fine, to keep them lubricated.
- Artificial tears are available as drops, gels and ointment. A number of products can be bought over the counter recommended by your optician.
Artificial tear drops and gels
- There are several types of artificial tear drops and gels. Occasionally, some people find one type may irritate. Changing to a different preparation may help if the first does not suit.
- At first it may be necessary to use them very frequently but when symptoms improve it may be possible to reduce application to three or four times per day.
- Gels are thicker than drops and may last longer. They do the same thing as the drops but you may not have to put them in as often.
- Some people develop sensitivity to the preservative used in artificial tears, especially if they are instilled frequently. Ask your pharmacist, optician or GP about preservative free artificial tears.
- Ointments are also available to help keep your eye moist overnight. When you sleep sometimes your eyes aren’t fully closed, so tears can evaporateand leave your eyes very dry when you wake up.
- Ointments tend to be used overnight because they are sticky and cause blurry vision.
- A combination of artificial tears throughout the day and ointment at night may be recommended.
Contact Lens Wearers
You should not wear contact lenses whilst using many types of eye drops. Check with your optician or pharmacist which artificial tears are suitable for use with contact lens wear.
Severe Dry Eye (Keratoconjunctivitis Sicca)
This is a more serious condition often related to systemic diseases e.g. rheumatoid arthritis or ‘Sjogrens’ syndrome. Sjogrens patients can have a very dry mouth and joint problems.
The eye is prone to develop ulcers and infections. In addition to the treatment above (including frequent preservative free drops and gel tears) your GP may refer you to an ophthalmologist for additional specialist treatment.
The College of Optometrists have a helpful website called ‘Look after your eyes’ which can be found at this link: http://lookafteryoureyes.org