BLOG: The scourge of preserved eye drops
Why do we prescribe topical medications that contain preservatives? Seriously.
In this day and age, why are we bathing the ocular surface with fluids that contain substances that produce inflammation on the cornea and the conjunctiva and, by extension, meibomian glands? Come on, folks, it’s 2020 for heaven’s sake. Do you know how benzalkonium chloride (BAK) is manufactured? It’s basically re-esterified tears from the eye of a newt. I guess that’s cooler than the original Healon (sodium hyaluronate, Johnson & Johnson Vision) being made from the cockscombs of roosters. Still, eye of newt is a basic ingredient in every evil witch’s brew.
Who really thinks putting something like that in your eyes is a good idea?
BAK is a highly effective preservative that leads to a very long shelf life for liquid medications. Unfortunately, it also causes both inflammatory dry eye disease and meibomian gland dysfunction. It is possible that the original insult is as mundane as a low-grade allergic reaction. However, most of the drop therapy we prescribe is continued over very long periods of time. Think glaucoma (see my upcoming November column in Ocular Surgery News). What starts off as a low-grade, minor irritant escalates into a raging inferno of inflammation.
People, we have options. It might be as simple as reducing the BAK burden on the surface of the eye by using fewer preserved drops. Pretty much every single ophthalmic compounding pharmacy has multi-med glaucoma and perioperative formulations. Each drop instilled contains most or all of the medicines your patient needs. For example, if you are a typical American cataract surgeon, you still prescribe a topical antibiotic, steroid and NSAID, each of which would typically be preserved with BAK. A compounded drop will still contain BAK; your patient is only putting in four doses of BAK each day instead of 12.
There are much more elegant solutions, though. The most frequently prescribed glaucoma medication is latanoprost, which comes as a generic made by at least a dozen companies, all of whom use BAK. Why are we not prescribing Xelpros? It doesn’t have BAK. Sun Pharma is super aggressive with market support; at the moment, I think it’s capped at $35 per month. OK, sure, that’s more than the $10 the generic costs. I’m as guilty of taking the low and easy road as everyone else. I can’t remember that last Xelpros prescription I wrote (note: I consult and speak for Sun). But is it really that difficult to convince our patients to pony up the extra 25 bucks for a healthier ocular surface? The same goes for other glaucoma drops. Why aren’t we fighting for our patients to get Zioptan and NP Cosopt, especially if they have symptomatic DED or MGD? Some companies already have tech that makes it possible to manufacture eye drops that don’t contain BAK. They might wanna get that out there before new companies like TearClear come along and steal their lunch money. But for the moment the onus is on us, the prescribing eye doctors, to choose better, safer versions of our topical medications. We must remember that non-preserved or alternately preserved options exist, and we must fight for our patients’ financial right to access them.
It’s up to us to prevent these inflammatory fires from starting in the first place.