- What to consider
- What to avoid
What to Consider
Artificial tears are eyedrops used to lubricate dry eyes and help maintain moisture on the outer surface of your eyes. They are available without a prescription. When choosing an OTC artificial tear to manage dry-eye symptoms, you need to know the underlying cause of your dry eye first. Based on that finding, you then consider other factors such as:
- Ingredients of the tear
- Common artificial tear ingredients include tonicity, buffering, viscosity, wetting, and lubricating agents; antioxidants; and preservatives[7]
- Good products should mimic the biphasic nature of tears by providing a lipid and an aqueous component to the tear
- Consulting with your doctor to find if you have more of an aqueous deficiency, mixed disease or an evaporative form of dry eye, then make the decision
- Choose products with lower osmolarity
- May have a better effect on the ocular surface based on some studies
- Tonicity agents adjust the preparation’s osmolality
- Choose products with Osmoprotectants
- Osmoprotectants L-carnitine and erythritol, alone or in combination, protect against stress activation of corneal epithelial cells cultured in hyperosmolar media
- They are taken up by cells, and they blunt the response of the epithelial cells on the surface of the eye to high osmolarity in the tears.
- Severity of symptoms
- Patients with mild dry eye
- May prefer a watery drop like Refresh Plus
- Problem with a watery drop
- Sometimes they really don’t last much longer than three to four minutes
- Patients with more severe dry eye
- May prefer a thicker drop that stays on the cornea longer.
- A thicker drop may decrease friction in the eye and lubricate the eye better
- “For more severe dry-eye patients and for patients who have many erosions on their corneal surface, I would prefer a thicker, more viscous drop, such as Refresh Celluvisc or Systane Ultra preservative-free,” Dr. Latkany says.[2]
- Problems with a thicker drop
- It tends to blur the vision because they are gooey and sticky
- Some people use them at night, but you can even have blurred vision for an hour or so after you wake up in the morning
- It leaves more residual foreign particles in the eye
- It allows allergens and other chemicals to stick to the tear film
- High-risk individuals, postmenopausal females, patients requiring 4 or more drops of artificial tears per day, and patients with rheumatologic conditions
- Should strongly be considered candidates for anti-inflammatory therapy.[6]
What to Avoid
“Self-selection of medications is not a good idea,” says Dr. Sheppard. “Invariably, when patients bring in their drops, they will be the Wal-Mart or Safeway brand of tears, which are by far the most inferior tears on the market.
Based on [2], here are the products to avoid:
- Topical vasoconstrictor like Visine
- Which induces vascular fragility, rebound vasodilation and dependence upon the vasoconstrictor to maintain a quiet, white-looking eye.
- Artificial tears using preservatives such as benzalkonium chloride (BAK)
- A recent study conducted at the University of Illinois at Chicago found that topical application of BAK to the eye causes:[2,9,10]
- Corneal neurotoxicity[10]
- Inflammation
- Reduced aqueous tear production
- After starting on an artificial tear, you needs frequent follow-up by eye doctors to determine whether the drop is relieving symptoms.
- Avoid using drops too frequent
- Patients were quoted to be using drops every 30 minutes or every hour, and this has a deleterious effect on their lifestyle and well-being.
- Be warned that artificial tears are helpful as adjunctive agents, but that they are not the answer for dry-eye patients.
- “None of these can come close to the complexity of our natural tears,” Dr. Latkany says.[2,13]
References
- Systane® lubricant eye drops in the management of ocular dryness
- OTC Drops: Telling the Tears Apart
- Dr. Sheppard says. “The hydroxypropyl-guar in Systane provides an excellent matrix for the aqueous component of the tear. Refresh Optive Advance as well as Soothe from Bausch + Lomb provide a lipid substitute to better stabilize the tear film. Another valuable additive to over-the-counter tears is hyaluronic acid, which can be found in Blink tears from Abbott,” he explains.
- Sarkar J, Chaudhary, Namavari A, et al. Corneal neurotoxicity due to topical benzalkonium chloride. Invest Ophthalmol Vis Sci 2012;53(4):1792-1802.
- Corrales RM, Luo L, Chang EY, Pflugfelder SC. Effects of osmoprotectants on hyperosmolar stress in cultured human corneal epithelial cells. Cornea 2008;27:574-579.
- Effect of systane and optive on aqueous tear evaporation in patients with dry eye disease.
- DRY EYE SYNDROME
- Power Graphics. Common ingredients in artificial tears. 1999;3(1):1–2.
- I have dry eyes. What should I look for when selecting artificial tears? (Mayo Clinic)
- Becquet F, Goldschild M, Moldovan MS, et al. Histopathological effects of topical ophthalmic preservatives on rat corneoconjunctival surface. Curr Eye Res. 1998;17:19-25;410–425.
- Corneal Neurotoxicity Due to Topical Benzalkonium Chloride
- Dry Eye: Proper Administration of Artificial Tears (Travel to Health)
- Oxidative Preservatives and Dry Eye
- The Microscopic Structures of Dried Human Tears
- Both tears of grief and joy are psychic tears, triggered by extreme emotions, whether positive or negative. Would a tear of grief look any different than a tear of joy?
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