An optometrist can diagnose the possible cause, but before you meet for your appointment, understand some of the common reasons for dry eye so you can identify possible reasons for your symptoms.
What is Dry Eye?
Dry eye disease is a common condition where there is an issue with your tear film, causing your eyes to be improperly lubricated.
The tear film is made of three layers: oil, aqueous fluid, and mucin, and an issue can arise when one doesn’t function as it should. Tears are dragged across your eyes to help keep them moisturized and smooth, but when the tear film is affected, you experience several aggravating or painful symptoms. Decreased tear production or increased tear evaporation are the most common causes of dry eye.
Dry eye causes
Decreased tear production
Tear production begins to decline as you age, and many adults 65 and older experience some symptoms of dry eye disease. This is not the only possible cause for inadequate tear production, as medications, medical conditions, and desensitized corneal nerves can contribute to dry eye as well.
This cause of dry eye is not as common as tear evaporation, but it can result in similar discomfort and disruption of your quality of life.
Increased tear evaporation
Your dry eye symptoms may be caused by increased evaporation of tears, usually caused by poor tear quality. When your tears are dragged across your eye, the oily layer of the tear film prevents evaporation.
This oil (or meibum) can become plugged, clogged, or be of poor quality, which can cause faster evaporation. When the glands releasing meibum become compromised, also known as meibomian gland dysfunction, this can lead to discomfort and inflammation.
This meibum can be affected by several other factors such as infrequent blinking, environmental factors, and eye allergies. Common causes of excessive tear evaporation include:
- Posterior blepharitis
- Wind, smoke, or dry air
- Vitamin A deficiency
- Eyelid problems (ectropion & entropion)
- Eye allergies
- Infrequent blinking
Knowing the main sources of dry eye disease is important, but you must understand the reasons for these causes as well. Understanding the reasons dry eye happens can help you have an idea of the cause of your symptoms before your appointment with your eye doctor.
Common Reasons for Dry Eye
While the symptoms of both causes of dry eye disease are similar, there are different reasons for why they occur. These reasons can include side effects from medications, medical conditions, allergies, and environmental factors.
Reasons for decreased tear production
Studies have shown an increasing prevalence of dry eye disease every five years after the age of 50, and dry eyes are a part of the aging process. Over time, we begin to develop fewer tears, which can lead to symptoms of dry eye.
Certain medications have side effects possibly contributing to your dry eye symptoms. These medications can include antihistamines, decongestants, and antidepressants. Common medications for acne and contraceptives such as birth control pills may cause these symptoms as well.
People who are affected by diabetes, thyroid problems, and rheumatoid arthritis may be more prone to developing dry eye. Medical conditions causing inflammation in the eyelids or surface of the eye may cause decreased tear production as well. Additionally, inward or outward-facing eyelids increase the risk of dry eye as well.
Your corneal nerves can become desensitized by contact lens use, nerve damage, or laser eye surgery. Typically, symptoms caused by laser eye surgery are temporary.
Reasons for increased tear evaporation
Your tears can be affected for a variety of reasons and can vary from medical conditions to environmental factors. If you are experiencing dry eye symptoms, consider some of the potential reasons:
Posterior blepharitis affects the inner edge of your eyelid. It is an inflammation of the eyelids where scale-like dandruff develops around the eye. This condition commonly occurs when your eyelid glands produce improper amounts of meibum, which can create an environment suited for bacterial growth. It can also be caused by other skin conditions such as rosacea.
Environmental & habitual factors
Environmental and habitual factors may contribute to dry eye as well. This can include smoke, wind, and dry air which may cause your tears to evaporate. A pair of wraparound sunglasses can protect your eyes during windy weather.
When you use the computer, you blink approximately 50% less than normal. When you blink your tears moisturize your eyes, so infrequently blinking while working on close-up tasks such as using the computer can cause dry eyes.
Conditions affecting your eyelids such as entropion and ectropion may contribute to dry eye disease. Entropion causes your eyelid to turn inwards and your eyelashes and skin to rub against your eye’s surface.
Ectropion is the opposite of entropion, causing your eyelid to turn outwards. This condition is common in older adults and causes your lower lid to pull away, causing improper tear drainage.
Allergens such as dander, dust, and pollen can irritate your eyes. Potential triggers for dry eye from allergies can include:
- Pet dander
- Diesel exhaust
- Dust mites
No matter the reason for your dry eyes, your optometrist can provide you with long-term relief through a variety of treatment options. If you suffer from dry eyes frequently, book an appointment with your optometrist.
Find Long-Term Relief
If you are experiencing symptoms of dry eye disease, your optometrist can provide you with a treatment plan suited for your unique needs. Contact your optometry office and find long-term relief for your dry eye symptoms.