Preservative-free treatment in glaucoma: who, when, and why?

Purpose: To review and summarize the available literature on the effect of preservatives on the eye, to provide practical guidance for the clinical assessment of the ocular surface in glaucoma patients, and to define patient populations that might benefit from preservative-free topical intraocular pressure (IOP)-lowering agents. Methods: This manuscript is based on a combination of a literature review on preservatives and the eye and expert opinion from glaucoma specialists with an interest in ocular surface disease. Results: There is an increasingly recognized association between eyedrop preservatives and ocular surface disease. Preservative-free therapy is now available for a wide range of active compounds, although there are still some misconceptions regarding their appropriate use. For patients treated topically for glaucoma or ocular hypertension, a rough estimate could be that 20% may need treatment with topical IOP-reducing agents that are free from preservatives. Conclusions: This review provides an up-to-date account of the literature regarding preservatives and the eye, as well as suggestions and recommendations on to when to use preservative-free antiglaucoma treatment.