Eyes need tears to stay healthy and comfortable. If the eyes do not produce enough tears, it is called dry eye. Dry eye is also when the eyes do not make the right type of tears or tear film.
When you blink, a film of tears spreads over the eye. This keeps the eye’s surface smooth and clear. The tear film is important for good vision. The tear film is made of three layers: An oily layer, A watery layer, A mucus layer.
Each layer of the tear film serves a purpose.
The oily layer is the outside of the tear film. It makes the tear surface smooth and keeps tears from drying up too quickly. This layer is made in the eye’s meibomian glands.
The watery layer is the middle of the tear film. It makes up most of what we see as tears. This layer cleans the eye, washing away particles that do not belong in the eye. This layer comes from the lacrimal glands in the eyelids.
The mucus layer is the inner layer of the tear film. This helps spread the watery layer over the eye’s surface, keeping it moist. Without mucus, tears would not stick to the eye. Mucus is made in the conjunctiva. This is the clear tissue covering the white of your eye and inside your eyelids.
Normally, our eyes constantly make tears to stay moist. If our eyes are irritated, or we cry, our eyes make a lot of tears. But, sometimes the eyes don’t make enough tears or something affects one or more layers of the tear film. In those cases, we end up with dry eyes.
Symptoms of dry eye.
- Eyes are stinging and burning.
- There is a scratchy or gritty feeling like something is in the eye
- There are strings of mucus in or around the eyes
- Eyes are red or irritated.
- It is painful to wear contact lenses
- Lots of tears in the eyes
Causes of dry eye.
- Certain diseases, such as rheumatoid arthritis, Sjögren’s syndrome, thyroid disease, and lupus
- Blepharitis (when eyelids are swollen or red)
- Entropion (when eyelids turn in); ectropion (eyelids turn outward)
- Being in smoke, wind or a very dry climate
- Looking at a computer for a long time (reduced blinking)
- Using contact lenses for a long time
- Having refractive eye surgery, such as LASIK
- Taking certain medicines, such as:
- Diuretics (water pills) for high blood pressure
- Beta-blockers, for heart problems or high blood pressure
- Allergy medicines (antihistamines)
- Sleeping pills
- Anxiety medicines
Dry Eye Treatments
Artificial tears. These are eye drops that are like real tears. A patient can use artificial tears as often as he needs to. There are many brands. Try a few until find a brand that works best for each case.
Ophthalmologist may suggest blocking tear ducts. This makes natural tears stay in the eyes longer. Tiny silicone or gel plugs (called punctal plugs) may be inserted in the tear ducts. These plugs can be removed later as needed. Ophthalmologist could also recommend surgery that permanently closes tear ducts.
Your ophthalmologist might have you use a special eyedrop medication. This helps the eyes make more of their own tears.
If eyes are irritated, ophthalmologist may recommend: prescription eye drops or ointments, warm compresses on the eyes, massaging your eyelids, certain eyelid cleaners.