What Is Dry Eye Disease?
Dry eye disease (DED) is a multifactorial condition in which the eyes do not produce a sufficient quantity or quality of tears to keep the eye surface properly lubricated. The tear film — a complex, layered film that covers the eye surface — is essential for eye comfort, health, and clear vision.
When the tear film is insufficient or unstable, the eye surface can become exposed and irritated, leading to the characteristic symptoms of dry eye.
Common Causes of Dry Eye
Aqueous-Deficient Dry Eye
This type occurs when the lacrimal glands do not produce enough watery component (aqueous layer) of the tear film. This can be related to ageing, autoimmune conditions such as Sjögren's syndrome, or inflammation of the lacrimal glands.
Evaporative Dry Eye (Most Common Type)
This is the most common type and occurs when tears evaporate too quickly from the eye surface. The most frequent cause is meibomian gland dysfunction (MGD) — a condition affecting the small oil-secreting glands along the eyelid margin. These glands produce the lipid (oily) layer of the tear film that slows evaporation. When they are blocked or dysfunctional, the tear film becomes less stable and evaporates more quickly.
Other Contributing Factors
- Ageing — Tear production naturally decreases with age, particularly after 50
- Hormonal changes — Particularly in postmenopausal women
- Screen use — Reduced blink rate during screen use leads to increased tear film evaporation
- Environment — Air conditioning, heating, wind, and low humidity
- Contact lens wear — Can disrupt the tear film and contribute to dry eye
- Medications — Including antihistamines, antidepressants, diuretics, and some blood pressure medications
- Autoimmune conditions — Such as rheumatoid arthritis, lupus, or Sjögren's syndrome
- Previous eye surgery — In some cases
Symptoms of Dry Eye
- A persistent sensation of dryness, stinging, burning, or grittiness
- Redness of the eyes
- Blurred vision that fluctuates — particularly when reading or using screens — and improves temporarily with blinking
- A feeling of something in the eye (foreign body sensation)
- Light sensitivity
- Excessive watering (reflex tearing)
- Eye fatigue or discomfort after sustained visual tasks
- Difficulty wearing contact lenses comfortably
Management of Dry Eye
Management is tailored to the underlying cause and severity. Common approaches include:
- Lubricant eye drops — Artificial tears help replace and supplement the tear film. Preservative-free formulations are preferred for regular use.
- Warm compresses and lid hygiene — Particularly important for meibomian gland dysfunction. Warm compresses soften the blocked oils, and lid cleaning removes debris from the lid margin.
- Environmental modifications — Using a humidifier, reducing air conditioning exposure, and ensuring good hydration
- Screen break strategies — The 20-20-20 rule: every 20 minutes, look at something 20 feet away for 20 seconds, and remember to blink fully
- Prescription medications — In moderate-to-severe cases, prescription anti-inflammatory eye drops or other therapies may be recommended
- Procedures — Various in-office procedures exist for meibomian gland dysfunction and are recommended in suitable cases
When Should You See an Eye Specialist?
If dry eye symptoms persist despite basic self-care, worsen over time, affect your ability to work or carry out daily activities, or are associated with redness, pain, or vision changes, a professional eye assessment is recommended. A thorough evaluation can identify the specific cause of your dry eye and guide appropriate management.