Dry eye: causes and prevention

10/02/2025

Dry eye is a common condition that affects millions of people worldwide. It occurs when the eyes do not produce enough tears or when tears evaporate too quickly, leading to a lack of lubrication on the eye's surface. This condition can cause significant discomfort, including burning, itching, a foreign body sensation, and blurred vision. While dry eye can be temporary, in some cases, it becomes a chronic issue that requires medical attention.

Causes of dry eye

Several factors can contribute to the development of dry eye. Below are the most common ones:

1. Reduced tear production: Over time, the glands responsible for producing tears may become less efficient. This decline is more common in older individuals and may result from aging or certain medical conditions, such as Sjögren’s syndrome, an autoimmune disease that affects the salivary and tear glands.
2. Excessive tear evaporation: Tears are essential for keeping the eye surface lubricated, but in some cases, they evaporate too quickly. When tear composition is imbalanced, its quality deteriorates, making it unstable and fragile. External factors such as air conditioning, wind, or prolonged exposure to screens and mobile phones negatively impact tear stability, further exacerbating dryness symptoms.

Blinking also plays a crucial role. This natural movement helps evenly distribute tears over the eye surface, ensuring proper protection and visual quality. On average, during a conversation, we blink about 15 times per minute, but when staring at screens, this rate decreases to just 5 times per minute. Blinking less frequently encourages tear evaporation.

3. Medication use: Certain medications can contribute to dry eye as a side effect. Antihistamines, decongestants, and some antidepressants are known to reduce tear production.
4. Environmental conditions: Climate factors, particularly in dry or highly polluted environments, can worsen dry eye symptoms. Wind, extreme cold or heat, smoke, and dust can irritate the eyes and increase tear instability.
5. Eye surgery: Refractive surgery, such as LASIK, can temporarily affect tear production, triggering dry eye symptoms in some individuals.
6. Contact lens use: People who wear contact lenses for extended periods are at a higher risk of developing dry eye, as lenses can alter tear distribution on the eye surface.

Prevention of dry eye

Preventing dry eye involves adopting measures that improve tear production and quality while reducing eye irritation. Some key recommendations include:

1. Proper hydration: Drinking enough water is essential to maintaining optimal tear levels. Dehydration can worsen dry eye symptoms.
2. Using humidifiers: In dry or heated environments, a humidifier can help maintain air moisture, preventing excessive tear evaporation.
3. Frequent screen breaks: People who spend long hours in front of a screen should follow the 20-20-20 rule: every 20 minutes, look at something 20 feet (6 meters) away for at least 20 seconds. This helps reduce eye strain and improves blinking, aiding in tear distribution.
4. Avoiding irritating environments: Reducing exposure to wind, smoke, and pollution can be beneficial. It is also advisable to limit excessive use of air conditioning or heating.
5. Using artificial tears: Artificial tears can provide temporary relief in cases of dry eye. These lubricating drops help keep the eye surface hydrated and alleviate symptoms.
6. Consulting a specialist: If symptoms persist or worsen, it is crucial to see an ophthalmologist. In some cases, specific medications, such as anti-inflammatory treatments, may be necessary to manage the condition effectively.

Conclusion

Dry eye is an uncomfortable condition that can significantly impact quality of life. However, with proper preventive measures and early diagnosis, its symptoms can be managed and alleviated. Adopting healthy habits and consulting a professional if symptoms persist are key steps in maintaining good eye health.

Dr. Rubén Delgado, Ophthalmologist at the Barraquer Ophthalmology Centre