Responses

Download PDFPDF
Efficacy and safety evaluation of benzalkonium chloride preserved eye-drops compared with alternatively preserved and preservative-free eye-drops in the treatment of glaucoma: a systematic review and meta-analysis
Compose Response

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.
Author Information
First or given name, e.g. 'Peter'.
Your last, or family, name, e.g. 'MacMoody'.
Your email address, e.g. higgs-boson@gmail.com
Your role and/or occupation, e.g. 'Orthopedic Surgeon'.
Your organization or institution (if applicable), e.g. 'Royal Free Hospital'.
Statement of Competing Interests

PLEASE NOTE:

  • Responses are moderated before posting and publication is at the absolute discretion of BMJ, however they are not peer-reviewed
  • Once published, you will not have the right to remove or edit your response. Removal or editing of responses is at BMJ's absolute discretion
  • If patients could recognise themselves, or anyone else could recognise a patient from your description, please obtain the patient's written consent to publication and send them to the editorial office before submitting your response [Patient consent forms]
  • By submitting this response you are agreeing to our full [Response terms and requirements]

Vertical Tabs

Other responses

Jump to comment:

  • Anastasios G Konstas, Gábor Holló, Andreas Katsanos, Konstadinos G Boboridis, Anna-Bettina Haidich and Gordon N Dutton
    Published on:
  • Published on:
    Is it really the same?
    • Anastasios G Konstas, Ophthalmologist 1st and 3rd University Departments of Ophthalmology, Aristotle University of Thessaloniki, Thessaloniki, Greece
    • Other Contributors:
      • Gábor Holló, Ophthalmologist
      • Andreas Katsanos, Ophthalmologist
      • Konstadinos G Boboridis, Ophthalmologist
      • Anna-Bettina Haidich, Biostatistician
      • Gordon N Dutton, Ophthalmologist

    Dear Editor,

    In their review and meta-analysis, Hedengran and coworkers1 report no relative therapeutic benefit of preservative-free (PF) therapies over benzalkonium chloride (BAK)-preserved ones. Should the costlier PF medications therefore be abandoned, or should we question this conclusion?
    Ten of the 16 comparative trials analysed were of short duration, (between 15 and 90 days), the longest taking 6 months. Once-a-day medication was used in each trial, yet the dose response curve for BAK toxicity shows that each additional drop of BAK-containing medication doubles the likelihood of lissamine green corneal staining2 and increases the risk of early failure of glaucoma surgery.3 BAK toxicity is slow in onset increasing over time, due to its continual accumulation within ocular tissues.3 Thus, inconsistencies between experimental studies, which document the harmful effects of BAK and clinical trials, which do not, likely relate to the timing, dosing and duration of glaucoma therapy.4 Two to 12 week trials comparing BAK with alternatively preserved eyedrops, or PF formulations have shown no convincing differences in ocular tolerability, yet the benefits from switching from once-a-day preserved to PF therapy, accrue several months later.4 Longer term transition to alternatively preserved, or PF formulations improves tolerability, and there is good evidence that substituting PF tafluprost for BAK-containing latanoprost significantly improves tolerability.3 So sh...

    Show More
    Conflict of Interest:
    None declared.