[2] This can be caused by age, contact lens use, meibomian gland dysfunction,[7] pregnancy, Sjögren syndrome, vitamin A deficiency, omega-3 fatty acid deficiency, LASIK surgery, and certain medications such as antihistamines, some blood pressure medication, hormone replacement therapy, and antidepressants.

The immunosuppressant cyclosporine (ciclosporin) may be recommended to increase tear production and, for short term use, topical corticosteroid medications are also sometimes helpful to reduce inflammation.

[4][13] Symptoms increase in windy, dusty or smoky (including cigarette smoke) areas, in dry environments high altitudes including airplanes, on days with low humidity, and in areas where an air conditioner (especially in a car), fan, heater, or even a hair dryer is being used.

[14] The most common cause of dry eye is increased evaporation of the tear film, typically as a result of meibomian gland dysfunction (MGD).

These glands often become clogged due to inflammation caused by blepharitis and/or rosacea, preventing an even distribution of oil.

[citation needed] In severe cases of MGD, the meibomian glands can atrophy and cease producing oil entirely.

[citation needed] Keratoconjunctivitis sicca can be caused by inadequate tear production from lacrimal hyposecretion.

[14] The lacrimal gland does not produce sufficient tears to keep the entire conjunctiva and cornea covered by a complete layer.

Other causes include congenital alacrima, xerophthalmia, lacrimal gland ablation, and sensory denervation.

[14] In rare cases, it may be a symptom of collagen vascular diseases, including relapsing polychondritis, rheumatoid arthritis, granulomatosis with polyangiitis, and systemic lupus erythematosus.

[13][14] Drugs such as isotretinoin, sedatives, diuretics, tricyclic antidepressants, antihypertensives, oral contraceptives, antihistamines, nasal decongestants, beta-blockers, phenothiazines, atropine, and pain relieving opiates such as morphine can cause or worsen this condition.

Only a small fraction of the estimated 1543 proteins in tears are differentially deficient or upregulated in dry eye, one of which is lacritin.

[23] Excess screen time on computers, smartphones, tablets, or other digital devices can cause dry eye.

[4] Several classes of medications (both prescription and OTC) have been hypothesized as a major cause of dry eye, especially in the elderly.

[15] In advanced cases, the epithelium undergoes pathologic changes, namely squamous metaplasia and loss of goblet cells.

In this test, the nasal mucosa is irritated with a cotton-tipped applicator, after which tear production is measured with a Whatman #41 filter paper.

[14] The presence of the recently described molecule Ap4A, naturally occurring in tears, is abnormally high in different states of ocular dryness.

Utilizing this technique it is possible to determine the concentrations of Ap4A in the tears of patients and in such way diagnose objectively if the samples are indicative of dry eye.

[37] Dry eyes can be worsened by smoky environments, dust, and indoor air conditioning, and by our natural tendency to reduce our blink rate when concentrating.

Purposefully blinking, especially during computer use and resting tired eyes are basic steps that can be taken to minimise discomfort.

[13] This includes avoiding hair dryers, heaters, air conditioners or fans, especially when these devices are directed toward the eyes.

Wearing glasses or directing gaze downward, for example, by lowering computer screens can be helpful to protect the eyes when aggravating environmental factors cannot be avoided.

[13] Most artificial tear fluids contain mucoadhesive polymers such as hyaluronic acid, cellulose derivatives or polyvinyl alcohol as lubricants.

[38] These polymers remain for a prolonged period of time on the ocular surface binding high amounts of water.

Evidence supporting this approach shows that autologous serum may be superior to artificial tears at relieving symptoms in the short-term, however, there is no strong evidence that autologous serum eye drops are better than artificial tears or saline solution for long-term symptom relief.

[42] Lubricating tear ointments can be used during the day, but they generally are used at bedtime due to poor vision after application.

[14] Specially designed glasses that form a moisture chamber around the eye may be used to create additional humidity.

[50] Diquafosol, an agonist of the P2Y2 purinergic receptor, is approved in Japan for managing dry eye disease by promoting secretion of fluid and mucin from cells in the conjunctiva, rather than by directly stimulating the lacrimal glands.

[52] Varenicline (Tyrvaya by Oyster Point Pharma) was approved by the US FDA for the treatment of dry eye disease in October 2021.

[4] People sometimes feel their vision blurs with use, or severe irritation to the point that they have trouble keeping their eyes open or they may not be able to work or drive.