By Satya Reddy, MD
The eye is bathed in tears, which provide nutrients and comfort. With each blink, tears are spread across the cornea, providing protection and clear vision. In a healthy eye, tears are produced at a slow, constant rate by the tear glands. Additionally, the eye can produce a watery tear at a rapid pace in response to irritants, like onions or pollen.
A healthy tear is composed of multiple layers: an outer lipid layer, middle water layer, and inner mucin layer. Each layer has a specific role. The inner mucin layer allows the tear to adhere to the surface of the eye. The outer lipid layer prevents rapid evaporation of the tear. The middle watery layer carries nutrients. Each layer is critical to vision, comfort, and ocular health.
Dry eye is a condition in which the tear film is inadequate either in quantity or quality. Symptoms of dry eye can include:
- Dryness
- Burning
- Sandy-gritty sensation
- Intermittent sharp, stabbing pain
- Tired eyes
- Redness
Dry eye syndrome can vary in severity because of many factors. As people age, tear production decreases. Women tend to produce fewer tears with hormonal changes associated with menopause. Environmental conditions are critically important in symptom severity. As humidity decreases, symptoms increase. For example, the dry air in Las Vegas can create much more eye discomfort than a Louisiana summer. Smoke and wind can exacerbate symptoms. Patients with any previous eye surgery can be more susceptible to the symptoms of dry eye – this can be very true of anyone who has undergone LASIK or any other laser vision correction.
Dry eye syndrome can be also a side effect of certain medications. Many over-the-counter and prescription medications can exacerbate dry eye. Any eyedrops used for allergies or “Get the Red Out” drops worsen dry eye. Although the eyedrop may provide transient relief from symptoms, the underlying dryness will worsen. Similarly, both OTC and prescription oral allergy medications reduce tear production. Prescription medications for high blood pressure and anti-depressants can worsen symptoms. Oral contraceptives can have similar side effects. Sometimes changing to a different brand or formulation can improve tear production. Frequently, post-menopausal women on hormone replacement therapy report lesser dry eye symptoms after initiating HRT.
Treatment options can be as basic as warm compresses to assist in cleaning the tear ducts along the eyelid to more involved medications or minor procedures. Frequently, over-the-counter artificial tears are sufficient for mild dry eye syndrome. Sometimes, small plugs are placed in the tear ducts to prevent excessive drainage of the tears, thereby increasing the moisture. Dietary supplements can improve the quality of the tears being produced. Certain medications can increase tear production. As dry eye syndrome can be progressive and develops over time, treatment options similarly can take several weeks to a few months to be effective. During this interim time, over-the-counter artificial tears can provide comfort.
Dry eye syndrome can be diagnosed by an ophthalmologist or optometrist during a comprehensive eye exam. Sometimes, special tests may be performed to better diagnose the condition. More substantial dry eye syndrome may be secondary to certain medical conditions. A thorough eye exam and medical history is required to best formulate a treatment plan for each patient.
