What is dry eye

Please note that all the pages on this website are intended for information only and do not constitute medical advice. For treatment recommendations and if symptoms persist, patients should consult their GP or other clinician. 

Feeling of Dry Eyes

The feeling of dry eyes is very common and can be quite debilitating for the sufferer. Various unpleasant sensations can be experienced:

  • feeling of dryness, grittiness, burning, itchiness or scratchiness of the eyes
  • sensitivity to light
  • blurred vision
  • excessive tear flow (caused by an imbalance in the tear film)

What about tears?

A sensation of dryness happens whenever the tear film becomes destabilised, breaks down and thus no longer lubricates the eye sufficiently. The tear film is a complex structure and has various functions:

  • It lubricates the surface of the eye
  • It keeps the surface tissue of the eye moist
  • It supplies nutrients and oxygen to the cornea
  • It hinders bacterial infections
  • It protects the eye from small dust particles

What happens when the tear film breaks down:

This usually happens because of a deficiency in the aqueous component of the tear film or an increase in tear evaporation, or a combination of these events.


The normal tear film

The dry eye tear film
 

What makes my eyes dry?

  1. 1. Environment:

    This feeling of dryness can have a variety of causes. These are often due to negative environmental influences.

    • Dry heat
    • Air conditioning
    • Dust or smoke
       

  2. Physical:

    But often the causes lie within the body itself:

    • The older we get the less tears are produced by our bodies.
    • Long hours in front of a computer screen, or...
    • ... the wearing of contact lenses, can destabilise the tear film.
    • Women can experience dryness in the eyes due to hormonal changes in the body.
       

  3. Medical:

    Underlying medical conditions that can effect the quality of tears:

    • Physical disorders in the body, such as rosacea, allergies, diabetes
    • Autoimmune diseases such as rheumatoid arthritis, lupus erythematosus, or Sjögren's Syndrome*
       

  4. Treatments:

    • Medication
    • Surgery that permanently changes the shape of the cornea
       

* Sjögren's syndrome:
For further information on this condition please visit the website of the British Sjögren's Syndrome Association.

Please consult a physician if you are concerned about any of these conditions.

An excellent summary of Dry Eye Disease can be found here: Dry Eye Fundamentals by Dry Eye Zone