Dry eye syndrome causes

Dry eye syndrome happens when your eyes stop making tears as they usually would. Tears are an important part of your eye health as they help to keep your eyes moisturised, protect them against infections, clear away any debris from the surface of your eyes and keep your vision clear. 

A normal tear film is made up of three main layers:

• Mucin layer – which lines the surface of the eye (the cornea) and makes the tears stick to the eye
• Aqueous (water) layer – this nourishes and protects the eye
• Lipid (oily) layer – this sits on the outer surface of the tear film and prevents the tears from evaporating.

A breakdown in the production of any of these layers will lead to an imbalance in the tear film, which reduces the quality or quantity of tears. For example, if the lipid layer is reduced, the tears may evaporate too quickly as there is nothing to hold the aqueous layer in place. If there is a reduced aqueous layer, not enough tears will be produced.

Dry eye syndrome can happen for many reasons, including any or a combination of the following:

• A blockage in the glands of the eyelid that supply the important oily layer of tears (known as meibomian gland dysfunction (MGD)) – without this layer (the lipid layer), the tears evaporate quicker, causing the eyes to dry out.
• Blepharitis – inflammation of the eyelid and around the eyelashes, which can also disrupt the glands responsible for producing the parts of the tear film
• Age – as we get older, our eyelids don’t spread tears across the eyes as well when blinking and the glands which supply the components of our tears can become less efficient (similar to when our skin dries more with age)
• Wearing contact lenses
• Working in an office or air-conditioned environment
• Computer eye strain – staring at a screen for a prolonged time means that we don’t blink as efficiently
• Some eye surgeries
• Being in a hot or windy environment
• Certain underlying medical conditions, like diabetes, rheumatoid arthritis or Sjögren's syndrome.
• Side effects of certain medications, such as some antihistamines
• Alcohol usage – alcohol can dehydrate the body and therefore reduce the volume of tears your eyes produce
• Hormonal changes, such as during the menopause or pregnancy.

Dry eye treatment

It’s fairly straightforward to treat dry eye syndrome and make your eyes feel more comfortable.

• Applying a heated eye mask to closed eyelids, twice a day for 10 minutes, can help to soften and loosen any blocked oil in the glands along the eyelid that supply oil into your tears.
  
  After you take off the eye mask, use a clean finger to gently massage your eyelids – this helps to get the oil flowing from the glands.

• Cleaning your eyelids each day with lid scrubs, wipes or foams can help to remove bacteria, debris and oil that can lead to blockage of the glands and dry eye syndrome.
• Using preservative-free dry eye drops (lubricants) can ease the symptoms. These drops can be used as often as needed, depending on your symptoms. Usually, you’d start using them two or three times a day.
  
  Dry eye drops will help with the symptoms, but it’s important to target the underlying causes of dry eye by carrying out steps one and two.
• If it’s thought that dry eye syndrome is caused by a medication you’re taking or an underlying medical condition, you should discuss this with your GP.
  
  If medication is aggravating symptoms, your GP may try switching you to an alternative. If your dry eye is thought to be caused by an underlying condition, then treating that condition will usually help to relieve the symptoms.
• If you’re a contact lens wearer, it can sometimes help to take a break from wearing your lenses or change to a different lens material.
  
  You could also use contact lens-friendly dry eye drops onto your lenses before you apply them each day, and then apply them during the day while you’re wearing your lenses.
• In more severe cases, surgery might be an option to prevent tears from draining away too easily, by plugging the tear duct which drains the tears.
• It has now been recognised that having a diet rich in Omega-3 fatty acids can help to manage dry eye syndrome. Omega-3 nutritional supplements can be effective as well. 

• Maintaining a good intake of fluid and making sure you don’t become dehydrated can help reduce the severity of dry eye syndrome.
• Avoiding smoky or very dry air-conditioned environments as much as possible can help with the symptoms of dry eye syndrome.