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.
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.
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.
Although dry eye may also redden the eyes, it requires different treatment from the condition known as 'red eye'.
Eye lubricants, also known as artificial tears, are used in the treatment of dry eye.
Artificial tears and eye lubricants are available as eye drops and ointments. These are the different types:
- Eye drops with preservative: these may be packaged in multi-dose containers with a preservative.
- Preservative-free eye drops: available in single-dose containers.
- Ointments: these are retained in the eye longer than drops because of their thicker consistency.
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.
If you need to apply eye lubricant frequently, it's generally recommended that you use preservative-free drops.
If you wear contact lenses, you should check with your optometrist or pharmacist that the product is compatible with the lenses, as some eye lubricants contain preservatives that may affect contact lenses.
Eye lubricants may have side effects:
- If you use eye drops/lubricant with preservative frequently, you may react to the preservative with symptoms such as stinging, burning and red eyes. If this is the case, you should switch to a preservative-free lubricant.
- Ointments may cause temporary blurring of vision. Because of this, some people use lubricant drops during daytime and an ointment at night.
- Unpleasant taste in your mouth.
- If you have a serious allergic reaction with symptoms such as hives or difficulty breathing, get emergency medical help by dialling 000. This is very rare.
Correct application of eye products
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.
In hot weather, it is preferable to store eye lubricants in the fridge. Single dose lubricant eye drops remain sterile until opened, if used within the expiry date printed on the packet. They are thrown away after one day's use.
Keep drops in a cool place away from the sun.
To apply drops:
- always wash your hands first;
- open the container, then pull the lower eyelid gently down with your forefinger to form a pocket;
- tilt your head slightly back and look up;
- holding the bottle between the thumb and forefinger, gently squeeze one drop into the lower eyelid pocket; and
- close your eyes for 1-2 minutes.
To apply ointment:
- hold the tube between the thumb and forefinger;
- tilt your head slightly back;
- pull down your lower eyelid gently to form a pocket;
- rest your hand against your nose to position the tip of the ointment tube aiming at the pocket;
- look up and away;
- apply a small strip of ointment into the lower eyelid pocket;
- blink gently and keep your eye closed for 1-2 minutes.
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
3. Mayo Clinic. Dry eyes. I have dry eyes. What should I look for when selecting artificial tears? Feb 2013. http://www.mayoclinic.org/diseases-conditions/dry-eyes/expert-answers/artificial-tears/faq-20058422 (accessed Sept 2015).
4. Drugs.com. Artificial tears. Revised July 2014. http://www.drugs.com/mtm/artificial-tears.html (accessed Sept 2015).