Reusing Dexamethasone Eye Drops Found Non-Contaminating

Research shows preservative-free dexamethasone eye drops can be safely reused within 24 hours, minimizing contamination risk.

To determine if repeated use of preservative-free dexamethasone 0.1% eye drops within 24 hours increases bacterial contamination.

Study Design: A prospective study involving 109 patients scheduled for corneal and glaucoma surgery, assessing bacterial contamination of eye drops used four times daily from the same vial.
Contamination Assessment: Bacterial contamination was evaluated by culturing drops at three time points: immediately after opening (t0), 10 hours later (t10), and 24 hours after opening (t24). Conjunctival swabs were taken before and after drop applications.

8.1% of drops were contaminated at t0, 11.8% at t10, and 10.0% at t24.
Contamination was more frequently attributed to fingertip flora rather than ocular surface flora.
In 5 of 21 contaminated cases, the same bacterial species were found in both the drop and the initial conjunctival swab.