Switching to preservative-free latanoprost: impact on tolerability and patient satisfaction

Dear editor

We read with interest the article by Negrete et al.¹ A recent study performed at our unit found similar results on conducting a review of tolerance to preservative-free latanoprost (Monopost) in patients who were unable to tolerate preserved formulae, and we would like to take the opportunity to share the results with you.

Notes were reviewed of 67 eyes in 35 patients started on Monopost who had shown intolerance to preserved latanoprost. It was noted that of these, only two were unable to continue the drug, demonstrating excellent tolerability. One patient stopped Monopost after 1 month, due to ocular surface discomfort. Another stopped after 7 months, as they felt the drops were the cause of their headache. The minimum follow-up was 8 months, with an average follow-up period of 15 months.

We also analyzed intraocular pressure (IOP) readings and found the mean to be 20.1 mmHg using preserved latanoprost and 18.7 mmHg 6 weeks after switching to Monopost. A paired-sample t-test and Wilcoxon signed-rank test were performed, which demonstrated no significant difference between the effectiveness of the treatments (P=0.68, P=0.117).

Given that these findings correlate well with the study by Negrete et al, we propose that it may not be necessary to perform an early IOP review 6 weeks after switching a patient from preserved latanoprost to Monopost, and so a patient could be followed up at their next routine glaucoma clinic visit.

This new preparation of latanoprost appears to provide, therefore, significant benefits to patients, as well as a useful therapeutic option for physicians, which is most welcome.

Disclosure

The authors report no conflicts of interest in this communication.