According to NHS Choices, around one in three people over the age of 65 suffer from dry eyes. In the majority of cases, it merely causes mild discomfort and doesn't pose any long-term health problems. However, in severe cases, it can be painful and lead to permanent damage to the front of the eye. Dry eye is caused by reduced or impaired tear production.

Some people don't produce enough tears, while others produce tears of a poor quality, such as an imbalance between the three layers of the tear film. Alternatively, some people suffer because the tears that are produced are not spread across the front of the eye properly.

For example, as people age, their eyelids may become less effective at spreading tears when they blink. Therefore, age is a risk factor for dry eye.

Other causes include:

• Hormonal changes, e.g. menopause
• Certain medicines, e.g. antihistamines
• Contact lenses
• Environment, e.g. exposure to smoke
• Prolonged reading or staring at a screen
• Pre-existing health conditions, e.g. rheumatoid arthritis and Sjogren's syndrome
• Surgery or an accident that permanently affects or scars the eyes
• An infection or inflammation of the glands around the eye, e.g. blepharitis.

Treating dry eye

Although there is no cure for dry eye, there are ways to help reduce symptoms:

Lifestyle changes such as lowering the temperature in a room or using a humidifier to ensure that the air isn't too dry. It's also important to blink frequently, which may be reduced when staring at a computer screen

Lubricant eye drops €“ dry eye sufferers often benefit from using eye drops called 'artificial tears'. These drops supplement natural tears and make the eyes feel more comfortable. Such products don't contain drugs so can be used frequently to alleviate symptoms. However, anyone who finds that they need to apply these drops more than four to six times a day should consider trying a different product.

There are various different brands available OTC and customers may need to try multiple products before they find one that works for them. OTC treatments include Murine Dry & Tired Eyes, Optrex Actimist Eye Spray, Rohto Dry Eye Relief and Systane Ultra Lubricant Eye Drops. Customers who have found several OTC treatments to be ineffective, or who feel like there is always something in their eyes, should be referred to the pharmacist.