Dry eye, also known as keratoconjunctivitis sicca (KCS), is an eye condition often resulting from decreased tear production or increased tear evaporation.
Dry eye is a fairly common condition, with studies suggesting that between 17 and 30% of individuals are effected at some point in their lives. It affects a disproportionately large amount of older people, and is more prevalent in women than men. Some medications, including diuretics, contraceptive pills and antidepressants, may also cause dry eyes as a side effect. Additionally, it may also be a symptom of a wider spread disease, such as arthritis.
Use of contact lenses may lead to dry eyes, though this can often be resolved by switching lenses or limiting use.
Common symptoms of a dry eye condition include – not surprisingly – dry eyes, as well as itching, burning, and an irritation described as sandy and gritty which worsens throughout the day. Pain, redness, pressure behind the eye, and sensitivity to bright light may also be symptoms of dry eye syndrome. Though it seems intuitively contradictory, dry eye syndrome may also cause eyes to water more than usual, though this watering will not necessarily ease discomfort. Vision can be affected and is often found to be variable in a dry eye patient.
Blinking aids in coating the eye with tears, so activities such as prolonged reading, computer usage, or television viewing, which decrease blinking, tend to worsen the effects of dry eye syndrome. Windy, smoky, and dusty areas, and dry environments including flights, air conditioned spaces, and low humidity locales, also exacerbate symptoms.
Typically dry eye syndrome creates only mild irritation without long-term effects. However, if left untreated, complications may arise causing eye damage, and eventually visual impairment.
Dry eye syndrome can often be diagnosed based solely on symptoms, though tests exist which measure the quantity and quality of tears. In mild to moderate cases, symptoms can be treated using lubricants, and through behaviours such as avoiding dusty, low humidity environments and direct exposure of the eyes to fans and hair dryers. There are lots of different lubricants available on the market however unfortunately, different lubricants work well for different people.
If symptoms persist, vision becomes blurred, or discomfort begins to impact day-to-day life, however, it is best to visit your optometrist, who can help identify the cause of your symptoms and suggest a course for treatment. In some cases this can be alternative medications to those already tried whilst for others it can be the temporary occlusion of the eye drainage channels.
Dry eye syndrome is not limited to humans, and can occur in dogs, cats, and horses as well. There are in fact many medications specifically for the purpose of non-humans.