Open drops in ophthalmology offices: expiration and contamination

Area of Science:

• Ophthalmology
• Microbiology
• Pharmaceutical Science

Background:

• Ophthalmic solutions are frequently used in clinical settings.
• Maintaining sterility of multi-use eye drops is crucial for patient safety.
• Previous studies have indicated potential contamination risks in ophthalmic preparations.

Purpose of the Study:

• To investigate the relationship between the usage patterns of eye drops and their contamination rates within ophthalmology practices.
• To assess the microbial quality of open eye drop bottles in clinical environments.

Main Methods:

• Collected open eye drop bottles from 18 ophthalmology offices after obtaining consent.
• Cultured nozzle tips and one drop from each bottle on solid media to detect bacterial growth.
• Evaluated bottle characteristics including drug category, volume, fill level, label legibility, and expiration date.

Main Results:

• Of 1,485 open bottles, 19.8% were expired. Glaucoma medications (16.4% of bottles) had a high expiration rate (33.7%).
• Expired bottles were more frequently associated with glaucoma drugs, smaller volumes (2-3 ml), near-empty containers, and visibly dirty bottles.
• Only one non-expired bottle of cyclopentolate yielded a low level of Micrococcus contamination (0.07%).

Conclusions:

• Eye drops in ophthalmology offices frequently exceed their expiration dates.
• Despite high expiration rates, the tested ophthalmic solutions demonstrated a low incidence of bacterial contamination.
• Clinical practices should focus on managing eye drop expiration dates to ensure optimal therapeutic efficacy and safety.