For 22 years preserved dorzolamide/timolol fixed combination (DTFC) has been a successful and popular option employed to meaningfully reduce intraocular pressure (IOP).

In trials DTFC shows equivalence to unfixed concomitant therapy; in real-life practice, however, it may prove superior owing to enhanced convenience, elimination of the washout effect from the second drop, improved tolerability, and better adherence.

A significant body of evidence has confirmed that DTFC offers uniform day and night IOP control with a favorable safety profile for the vast majority of treated patients.

More evidence is needed on the transition to DTFC in patients insufficiently controlled with prostaglandin monotherapies and the precise role and timing of DTFC in the glaucoma treatment algorithm.

Cumulative evidence has confirmed that preservative-free (PF) DTFC is at least equivalent in efficacy to preserved DTFC and provides tangible clinical benefits to patients with glaucoma suffering from ocular surface disease (OSD) by improving tolerability and adherence.

In the future PF DTFC will further enhance its role in glaucoma therapy algorithms if controlled evidence demonstrates the long-term value of PF medications.