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Ocular surface toxicity from glaucoma topical medications and associated preservatives such as benzalkonium chloride

Alberto Aguayo Bonniard1, Jacky Y Yeung1,2, Clara C Chan1

  • 1a Department of Ophthalmology and Vision Sciences , University of Toronto , Toronto , Canada.

Expert Opinion on Drug Metabolism & Toxicology
|July 12, 2016
PubMed
Abstract

Insights

Topical glaucoma medications can harm the ocular surface due to preservatives like benzalkonium chloride. Minimizing exposure to this preservative can improve treatment outcomes for glaucoma patients.

Area of Science:

  • Ophthalmology
  • Ocular Surface Disease
  • Glaucoma Management

Background:

  • Topical anti-glaucoma medications are essential for managing chronic glaucoma globally.
  • However, their benefits are often offset by corneal and conjunctival toxicity caused by preservatives.
  • Benzalkonium chloride (BAC) is a common preservative with known adverse effects.

Purpose of the Study:

  • To review the evidence on the impact of topical medications and preservatives on the ocular surface in glaucoma patients.
  • To examine the effects of benzalkonium chloride on ocular surface histopathology and clinical outcomes.
  • To discuss the relationship between ocular surface disease and benzalkonium chloride exposure.

Main Methods:

  • Review of basic science and clinical evidence regarding topical ocular drops and preservatives.
  • Analysis of the effects of benzalkonium chloride versus non-benzalkonium chloride preserved drops.
  • Examination of conjunctival histopathology and its clinical implications.

Main Results:

  • Benzalkonium chloride contributes to ocular surface toxicity, impacting the cornea and conjunctiva.
  • Ocular surface disease is linked to benzalkonium chloride exposure.
  • Adverse effects of preservatives can negatively affect patient quality of life.

Conclusions:

  • Topical anti-glaucoma medications will remain crucial for glaucoma treatment.
  • Reducing exposure to benzalkonium chloride is key to improving treatment outcomes.
  • Alternative preservatives, preservative-free options, and novel drug delivery systems are needed for better glaucoma patient care.
Keywords:
Benzalkonium chlorideconjunctivacorneaglaucomapreservativestoxicity

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