Dry, gritty eyes: causes, red flags and when to get it checked

The surface of the eye relies on a thin film of tears made of water, oil and mucus. If any layer is deficient or unstable, the surface dries and becomes irritated, giving a gritty, burning or foreign-body feeling. Most often the oil layer is deficient because the glands in the eyelid margins are blocked.

• Meibomian gland dysfunction and blepharitis: crusty, sticky lashes, red lid margins and symptoms worst in the morning.

• Screen use, reading and concentrating, which reduce blink rate; also air conditioning, heating and wind.

• Contact lens wear and ageing, with tear production falling gradually, particularly in women after menopause.

• Medicines that dry the eyes: antihistamines, antidepressants, some blood pressure drugs, isotretinoin and HRT-related changes.

• Allergic conjunctivitis with itchy, watery eyes and seasonal pattern.

• Autoimmune disease: Sjogren syndrome, with dry mouth too, and rheumatoid arthritis.

• Incomplete eyelid closure, thyroid eye disease and previous eye surgery.

• Infection or corneal damage, which usually has pain, redness and light sensitivity.

Severe pain, marked light sensitivity, reduced vision, a white spot on the cornea, a very red eye, or a gritty eye after a chemical splash, welding or metal fragments should not be treated as simple dryness. Dry mouth, joint pain and unusual tiredness suggest a systemic cause.

• Go to A&E or an emergency eye service now: chemical splash, or a sharp object or metal fragment injury to the eye.

• Same-day eye assessment: painful red eye, light sensitivity or reduced vision, especially if you wear contact lenses.

• GP or optometrist within weeks: dry eyes with a dry mouth, joint pain or rash.

• Pharmacist or routine optometrist: gritty eyes that are mild and worse on screens.

They ask about screen time, contact lens use, medicines, menopause, joint and mouth symptoms, and what makes it better or worse. Examination includes the lid margins and glands, tear film stability, staining of the eye surface and the quality of the tear layer.

• Tear break-up time: measures how quickly the tear film becomes unstable.

• Fluorescein or lissamine green staining: shows damage on the eye surface.

• Schirmer test: measures tear volume.

• Blood tests for Sjogren and other autoimmune markers, if systemic features are present.

Use preservative-free lubricating drops several times a day, a daily warm compress and gentle lid cleaning for blepharitis, and take regular screen breaks with deliberate blinking. Keep air humid where possible and drink fluids. Omega-3 supplements have mixed evidence. Wear contact lenses for shorter periods.

An optometrist or pharmacist is the usual first stop. Persistent or severe cases go to an ophthalmologist, and private dry-eye clinics offer treatments such as intense pulsed light and gland expression.