Preservative exposure
Benzalkonium chloride remains in many generic glaucoma drops and is linked to irritation and inflammation of the surface.
Glaucoma Care · Ocular Surface
Ocular Surface Care in Glaucoma Comfortable eyes keep patients on their drops.
Long-term drop use and preservatives take a toll on the tear film, and a patient whose eyes burn is a patient who skips doses. Screening glaucoma patients for surface disease, and treating it, protects both comfort and pressure control.
59%of glaucoma patients with dry eye symptoms in Leung 2008
48.4%with some degree of surface disease in Fechtner 2010
630patients across ten sites in the Fechtner study
BAKthe preservative most tied to surface toxicity
Why it happens
Where the surface damage comes from
Glaucoma patients are often older, use drops for years and frequently use more than one bottle, so several stresses on the tear film add up.
Drop burden
Surface disease tends to be worse in patients using more than one glaucoma medication each day.
Age and comorbidity
Meibomian gland dysfunction, blepharitis, rosacea and allergy are common in the same age group and compound symptoms.
Adherence risk
Burning and redness after instillation give patients a reason to skip doses, which undermines pressure control.
Options that reduce the load
The aim is fewer preserved drops and a healthier surface, without giving up pressure control.
- Switch to preservative-free or alternative preservatives
- Reduce the number of bottles
- Treat the lids and tear film directly
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Preservative-free agents
Preservative-free timolol, latanoprost, tafluprost and dorzolamide-timolol are available, as are drops with alternative preservatives.
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Fewer bottles
Fixed combinations, selective laser trabeculoplasty or an intracameral implant can cut the number of daily drops.
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Surface therapy
Preservative-free artificial tears, lid hygiene, warm compresses and, where indicated, prescription anti-inflammatory dry eye drops.
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Punctal plugs with caution
Occlusion keeps tears on the eye but can also keep more glaucoma drug there, so weigh it against side effects.
In the clinic
Screen every glaucoma visit
Build a short surface check into the glaucoma follow-up rather than waiting for complaints.
Ask
Use a symptom questionnaire such as the OSDI and ask directly about burning and missed doses.
Look
Check lid margins, meibomian glands, tear breakup and corneal and conjunctival staining at the slit lamp.
Adjust
Change the formulation or regimen, start surface treatment, and recheck both pressure and comfort at the next visit.
Practical references
Common changes and why
| Preserved to preservative-free | Removes BAK exposure from the most-used bottle |
|---|---|
| Two bottles to a fixed combination | Halves the number of instillations for the same two classes |
| Drops to laser | SLT can reduce or replace drops for many patients |
| Drops to implant | Durysta or iDose TR deliver drug inside the eye for eligible patients |
| Add PF artificial tears | Supports the tear film between glaucoma doses |
Products practices stock for these patients
- Preservative-free lubricant drops in multi-dose bottles or single-use vials
- Gels and ointments for nighttime use
- Hypochlorous and tea tree lid cleansers
- Heat masks for meibomian gland dysfunction
Spacing drops
Advise patients to wait at least five minutes between different eye drops so one does not wash out the next, and to use artificial tears separately from glaucoma doses.
Questions about surface care in glaucoma
How common is surface disease in glaucoma patients?
In Leung and colleagues' study, 59% of glaucoma patients reported dry eye symptoms. Fechtner and colleagues found 48.4% of 630 patients had some degree of surface disease.
Should every patient switch to preservative-free?
Not necessarily. Prioritize patients with symptoms, staining or several daily bottles, and those whose adherence is slipping.
Can artificial tears be used with glaucoma drops?
Yes, spaced several minutes apart. Preservative-free tears avoid adding more preservative exposure.
Do punctal plugs help?
They can improve tear volume, but they may also increase the amount of glaucoma drug that stays in contact with the eye. Use them with that trade-off in mind.
When should drop burden be reduced with a procedure?
When surface disease or adherence limits medical therapy, laser trabeculoplasty, an implant or MIGS are options to discuss with the surgical partner.
Which surface products can patients buy through my practice?
Preservative-free tears, lid hygiene and heat masks are available at wholesale, and RescueLink lets you send them to patients between visits with a 15% participation credit on eligible OTC orders.
References
- Leung EW, Medeiros FA, Weinreb RN. Prevalence of ocular surface disease in glaucoma patients. J Glaucoma. 2008;17(5):350-355. Review citing study
- Fechtner RD, et al. Prevalence of ocular surface complaints in patients with glaucoma using topical IOP-lowering medications. Cornea. 2010;29(6):618-621. Review citing study
- Ophthalmology Management. Dry eye and glaucoma patients, July 2024. Article
Protect the surface, protect adherence
Stock preservative-free tears and lid care, and send them to glaucoma patients between visits with RescueLink.
Written for licensed eye care professionals. Treatment decisions remain with the treating doctor. Review each product's labeling before use. The RescueLink participation credit applies to eligible OTC orders on VisionRescue.com; contact lenses and prescriptions are excluded.