What is dry eye?
Dry eye is a term used when the eye does not produce tears that lubricate the eye adequately. There may not be enough tears, or the tears produced may not have sufficient lubricating qualities.
- The eyes feel dry, gritty and sore, but not painful.
- The eyes may be sensitive to light.
- The eyes may become red.
- The irritation caused by dry eye may trigger excessive tears, causing watery eyes.
- Blurred vision.
Dry eye may be caused by:
- eye allergies;
- diseases such as rheumatoid arthritis, scleroderma, or Sjogren's syndrome that disrupt the normal production of tears;
- some medicines such as antihistamines, benzodiazepines, diuretics, oral contraceptives, oestrogen hormone replacement therapy, antipsychotics and tricyclic antidepressants, and
- environmental factors such as low humidity, wind or dry air, causing tear evaporation.
How can you help?
You can help prevent dry eye by:
- protecting your eyes from sun and wind by wearing wrap-around sunglasses;
- avoiding irritants such as smoke, dust, cosmetics and chlorine;
- avoiding air conditioners that dry the air;
- avoiding hair dryers blowing into your eyes;
- using a humidifier at home;
- increasing your intake of omega-3 fatty acids (either through diet or supplements);
- using artificial tears or lubricant regularly;
- eating a healthy diet; and
- treating any blepharitis.
Although dry eye may also redden the eyes, it requires different treatment from the condition known as 'red eye'.
Dry eye symptoms should be treated because if the eye is not properly lubricated, foreign material not washed away from the eye may lead to eye damage, infection and ulceration.
Artificial tears and lubricants are available as eye drops, gels and ointments. Eye drops are ideal for regular use during the day, and can be used as often as you need them. Ointments or gels may be used at night, or for severe daytime symptoms. Some people can be allergic to the preservative used in eye drops; if so, preservative-free preparations are available, although they are more expensive.
You should always wash your hands before instilling eye drops or applying eye ointment or gel. Be careful not to touch the eye with the container, as the contents may become contaminated with bacteria and later cause infection. Discard any unused medication once the packet has been open for 4 weeks.
Blepharitis, which is a condition causing lid inflammation and poor tear production needs specific treatment.
Dry eye raises the risk of eye infections, because the surface of the eye is not protected adequately by tears.
Severe dry eyes may lead to inflammation of the eye and scratching of the corneal surface.
When should you seek medical advice?
You should seek medical advice if:
- the eye is painful;
- eyesight is deteriorating;
- vision is blurred;
- the eye is red;
- the eye has a coloured discharge;
- the eyelids are stuck together on waking; or
- the dry eye persists for 7 to 10 days, despite treatment.
Eye lubricants successfully alleviate the symptoms of dry eye but do not cure the cause. You should see your doctor urgently if the eye becomes red and painful and/or your vision becomes blurry.
2. National Eye Institute, National Institutes of Health. Facts about dry eye [updated Feb 2013; accessed Sept 2015]. Available from: http://www.nei.nih.gov/health/dryeye/dryeye