What is Dry Eye Syndrome?
Dry eye syndrome (also called dry eye disease or keratoconjunctivitis sicca) is a multifactorial disorder of the tear film and ocular surface. The tear film consists of three layers — an outer lipid layer (produced by the meibomian glands), a middle aqueous layer (produced by the lacrimal gland), and an inner mucin layer (produced by goblet cells of the conjunctiva). Disruption of any of these layers leads to tear film instability, increased evaporation, and inflammation of the ocular surface. The condition is broadly classified into two categories: aqueous deficient dry eye (insufficient tear production) and evaporative dry eye (excessive tear evaporation, most commonly due to meibomian gland dysfunction). Many patients have a combination of both. Dry eye is extremely prevalent, affecting up to 30% of the population over age 50, and its incidence is rising due to increased screen time and environmental factors.
Symptoms
- Stinging, burning, or scratchy sensation in the eyes
- A feeling of having something in the eye (foreign body sensation)
- Redness and irritation
- Stringy mucus in or around the eyes
- Blurred vision that fluctuates with blinking
- Eye fatigue, especially after prolonged reading or screen use
- Paradoxical excessive tearing (reflex tearing in response to dryness)
- Difficulty wearing contact lenses
- Sensitivity to light
Causes and Risk Factors
Dry eye results from an imbalance in tear production, composition, or drainage. Common causes and risk factors include:
- Aging — tear production naturally decreases with age
- Hormonal changes, particularly in postmenopausal women
- Meibomian gland dysfunction (MGD) — the leading cause of evaporative dry eye
- Prolonged screen use (reduced blink rate)
- Dry, windy, or air-conditioned environments
- Contact lens wear
- Medications — antihistamines, decongestants, antidepressants, hormone replacement therapy, and beta-blockers
- Autoimmune diseases — Sjögren's syndrome, rheumatoid arthritis, lupus
- Previous eye surgery (e.g., LASIK)
- Vitamin A deficiency
Diagnosis
Diagnosis is based on ocular surface staining with fluorescein, which reveals areas of epithelial damage on the cornea and conjunctiva.
Treatment
Treatment is tailored to the type and severity of dry eye and often involves a stepwise approach:
- Artificial tears and lubricating eye drops — preservative-free formulations are preferred for frequent use
- Warm compresses and lid hygiene — especially for meibomian gland dysfunction
- Anti-inflammatory therapy — topical cyclosporine A (Restasis) or lifitegrast (Xiidra) to address underlying ocular surface inflammation
- Punctal plugs — small devices inserted into the tear drainage ducts to retain tears on the ocular surface
- Omega-3 fatty acid supplementation to support healthy meibomian gland secretion
- Intense pulsed light (IPL) therapy for meibomian gland dysfunction
- Autologous serum tears for severe cases unresponsive to conventional therapy
- Environmental modifications — humidifiers, avoiding direct airflow, and taking regular screen breaks (20-20-20 rule)
Prevention and Recommendations
- Follow the 20-20-20 rule: every 20 minutes, look at something 20 feet away for 20 seconds
- Blink consciously and fully, especially during screen use
- Use a humidifier in dry or air-conditioned environments
- Stay well hydrated by drinking adequate water throughout the day
- Wear wraparound sunglasses in windy or dusty conditions
- Include omega-3-rich foods in your diet (fish, flaxseed, walnuts)
- Avoid smoking and exposure to secondhand smoke
- Review your medications with your doctor if you experience persistent dryness