What is dry eye?

Normally your eyes are kept moist by the tears that bathe the surface. The action of blinking spreads the tears across the surface of your eyes. Tears contain important substances that lubricate the eyes, prevent infection and slow down evaporation of the tears.

Dry eye can occur for several reasons – either because you do not make enough tears or because your tears evaporate too quickly. Symptoms can include irritation, gritty burning, inflamed eyes, resulting in ocular surface damage.

Dry eye is one of the most common of all eye conditions. Although it particularly affects older people, it can occur at any age. It is also more common in women.

What are the symptoms of dry eye?

Stinging, burning or a gritty feeling in your eyes are common symptoms. Your eyes may feel slightly red, feel heavy and become sensitive to bright light. Stringy mucus may collect on the lids. Symptoms may be less when you first wake up, but get worse as the day goes on.

Fortunately, dry eye is unlikely to affect your sight. However, if your eyes are very dry, for example if you do not even produce tears in emotional situations or as a reaction to peeling onions, the symptoms may be intolerable.

What causes dry eye? 

  • Ageing
  • Eye strain due to prolonged computer use
  • Anything that interferes with the blinking mechanism or the ability to close the eye properly at night
  • Contact lens wear
  • Hormonal changes during pregnancy and menopause
  • Environmental factors (e.g wind, smoke, heat, higher altitude and dry air blowing from air conditioners and heaters
  • Certain diseases and health conditions such as arthritis, diabetes and lupus
  • Certain medication such as HRT, antihistamines, antidepressants, oral contraceptives, blood pressure medication and acne medication