Dry eye

Also called Dry eye disease, Blepharitis

Extremely common, chronically under-treated, and drops alone usually miss the actual cause.

What it is

Dry eye affects a very large number of adults, rising sharply with age and considerably commoner in women after the menopause.

The name misleads. In the majority of cases the problem is not a lack of tears but a lack of the oil layer that stops tears evaporating. That oil comes from the meibomian glands in the eyelids, and when they block, tears evaporate too quickly.

Which means lubricating drops treat the symptom while the blocked glands continue. Warm compresses and lid hygiene treat the cause, and almost nobody does them consistently or for long enough.

Screens make it worse because blink rate drops substantially while concentrating.

Signs you might notice

Gritty, burning, tired eyes, worse through the day.

Watery eyes, which is counterintuitive and very common: the irritation triggers reflex tearing.

Blurred vision that clears on blinking.

Crusting or redness of the lid margins.

Contact lenses becoming uncomfortable.

Severe pain, light sensitivity or reduced vision means something else and needs same-day assessment.

How it can affect day-to-day life

In older people and people with reduced blink or incomplete lid closure, from Bell's palsy, stroke, or sedation, dry eye can cause corneal damage rather than just discomfort. Eye care in those situations is a clinical task, not a comfort measure.

Many common medicines cause it: antihistamines, some antidepressants, diuretics, and isotretinoin.

Persistent dry eye with a dry mouth may be Sjögren's syndrome and warrants investigation.

Supporting someone well

Do warm compresses properly: a genuinely warm compress held for around ten minutes, then gentle lid massage and cleaning, daily, for at least six weeks. Thirty seconds with a flannel does nothing.

Use preservative-free drops if using them more than four times a day; preservatives themselves irritate.

Blink deliberately and take screen breaks. Position screens below eye level to reduce the exposed surface.

Review medication.

For anybody who cannot close their eyes fully, use ointment at night and consider taping. This prevents corneal damage.

Check for dry mouth alongside, and mention it, since the combination changes the diagnosis.

Where to get help

An optometrist can assess and advise, and many now offer specific meibomian gland treatments.

A GP for persistent symptoms, or where an underlying condition is suspected.

Pain, light sensitivity or visual loss needs same-day assessment.