An Overview of Preservative Free Eye Drops Available in Canada
Dry eyes are one of the most common complaints that patients present with at their eye exam appointment and they often ask our Optometrists for a recommendation on which eye drop will be he best at treating their symptoms. Due to the variety of choices available on the market, many patients have tried several types of eye drops and may have had inconsistent or poor results in the past. In this article we will go over the different classes of eye drops and the important ingredients we want them to contain (or in some cases to avoid!).
Preservative Free Eye Drops Are Recommended
The first thing we want to do when looking over the ingredients list of an eye drop bottle is to check to see if the product contains preservatives. While small amounts of preservatives are generally well tolerated, regular use of eye drops containing them can actually increase irritation to the ocular surface and worsen dry eye symptoms. BAK or benzalkonium chloride is an antimicrobial surfactant that has been used in many eye drops since the 1950s. While its proven to be an effective antimicrobial agent it can be allergenic to some patients and is known to be an irritant (1). Polyquad is a derivative of BAK and is also used in many eye drops and also has known cytotoxic effects (2). Some patients who have glaucoma have no option but to take prescription glaucoma medications like Travatan-Z that are preserved with BAK or Polyquad and that is OK because the risk of glaucoma far outweighs the issues with irritation of the eye surface in most cases. Its important to consult with your eye doctor about the best eye drops for you.
I-MED Pharmaceuticals I-DROP PUR, I-DROP PUR GEL, and I-DROP MGD
When there is an option available, preservative free is favored as we don’t have to worry about potential irritation or allergic response due to preservatives. I-MED Pharmaceuticals, based in Quebec, Canada has currently has three excellent options for preservative free artificial tears with their line of I-DROP products. I-DROP PUR is an excellent every day use eye drop that is contact lens compatible and contains hyaluronate for long lasting moisturization. Many patients with mild to moderate dry eye symptoms; for example computer users, allergy sufferers, and people who work in dusty environments use I-DROP PUR 3-4 times per day as part of their daily routine. For those with more advanced dry eye we recommend I-DROP PUR Gel which contains a higher concentration of hyaluronate for relief. While I-DROP PUR gel is very effective with reducing dry eye symptoms, it may cause slightly more temporary blurring of vision upon instillation due to its high viscosity and is not contact lens compatible. The latest addition to I-MED’s portfolio is I-DROP MGD, which contains a lipid layer enhancer in addition to hyaluronate to help patients with evaporative dry eye caused by meibomian gland dysfunction (MGD). MGD is one of the most common causes of dry eye symptoms and when combined with warm compresses and Omega 3 supplementation, I-DROP MGD has been very effective in its treatment.
Labtician-Thea: Hyabak and Thealoz Duo
Hyabak by Labtician-Thea is another great choice for every day relief from mild to moderate dry eye. Hyabak eye drops contain hyaluronate which attracts water molecules and keeps the ocular surface moisturized. Thealoz Duo which is formulated with the unique combination of Trehalose and Hyaluronate is the most advanced formulated offered by Labtician-Thea. Trehalose is a naturally occurring polysaccharide which has documented cell membrane stabilization properties. In the context of dry eye, it helps to reduce the foreign body sensation experienced by some dry eye sufferers who feel like their eyes are gritty or their sand stuck in their eyes. With the one-two punch of hyaluronate and trehalose, Thealoz Duo is one of the most popular eye drops worldwide. Thealoz Duo Gel is also available for more aggressive forms of dry eye with the addition of a carbomer for longer lasting protection. Thealoz Duo Gel is dispensed in individual vials.
Aequus Pharmaceutical – Evolve Eye Drops
The Evolve line of eye drops includes Evolve Daily Intensive and Intensive Gel and is a new option available as of 2021 in Canada. Both eye drops are preservative free and contain hyaluronate. Evolve Daily Intensive has 0.20% hyaluronate and is safe to use with contact lens. For advanced dry eye relief, Evolve Intensive Gel combines hyaluronate with the addition of Carbomer-980 a proprietary polymer that acts like a net for water molecules, attracting them to the ocular surface to hydrate the eyes. Intensive Gel also contains glycerol to help balance the osmolarity of the tear film.
Merchel Piovesan Pereira B, Tagkopoulos I. Benzalkonium Chlorides: Uses, Regulatory Status, and Microbial Resistance. Appl Environ Microbiol. 2019;85(13):e00377-19. Published 2019 Jun 17. doi:10.1128/AEM.00377-19
Paimela T, Ryhänen T, Kauppinen A, Marttila L, Salminen A, Kaarniranta K. The preservative polyquaternium-1 increases cytoxicity and NF-kappaB linked inflammation in human corneal epithelial cells. Mol Vis. 2012;18:1189-1196.