Lubricant drops & Artificial tears. Ocular lubricant drops, also known as artificial tears are the most common form of dry eye control. They work in their simplest form by increasing the tear layer and creating a barrier between the lids and the eye surface.
There are many types of lubricating drops available. What sets them apart is in the way they work in addition to the tear volume described above. Additional components work to mimic the natural tears in nutrient composition, lubricity, salt components. They are therefore acting as tear substitutes, continuing to do the job that our natural tears would otherwise be doing.
These additional components can try and mimic different parts of the tear film, the three basic layers being mucin, lacrima and meibum, and taking this further, manufacturers are developing drops that stay in the eyes for longer, reducing the number of times you will need to put them in your eyes over the day.
Some of the novel ingredients come from Cactii and Tamarind seed. These components work to support the mucin layer which is the base layer in contact with the epithelial cells on the eyes surface.
And finally there is the length of time the drops last in the bottle. Previously, most artificial tears were preserved. The preservative use, Benzalkonium chloride (BAK) has the long been known to actually cause dry eye itself over long term use. More and more manufacturers have been changing to either non preserved or disappearing preservative formulations.
You might be wondering wy they dont make all eye drops in this way. I wondered the same thing and asked some of these manufacturers. The silicon used as part of the filter in the bottle reacts with these medications and the cost of adapting the design increases the end cost of the product. Not good news for patients or the NHS!