Stability of cefazolin sodium eye drops

Area of Science:

• Ophthalmology
• Pharmaceutical Sciences
• Microbiology

Background:

• Cefazolin sodium is an antibiotic commonly used in ophthalmic preparations.
• The stability of extemporaneously prepared cefazolin sodium eye drops is crucial for effective treatment and patient safety.

Purpose of the Study:

• To assess the stability of cefazolin sodium in both preservative-free and preservative-containing ophthalmic formulations.
• To determine optimal storage conditions for extemporaneously prepared cefazolin eye drops.

Main Methods:

• Extemporaneous eye drop formulations of cefazolin sodium were prepared.
• Stability-indicating High-Performance Liquid Chromatography (HPLC) was used to monitor cefazolin sodium concentrations.
• pH, osmolality, and microbial contamination were assessed under different storage conditions (refrigerated vs. room temperature).

Main Results:

• Cefazolin sodium eye drops remained stable for 42 days when stored at 4°C with minimal changes in pH and osmolality.
• Eye drops stored at room temperature showed instability within a few days, with significant pH and osmolality shifts.
• No bacterial or fungal growth was detected in any samples after 7 days of incubation, indicating initial sterility.

Conclusions:

• Extemporaneously prepared cefazolin sodium eye drops exhibit limited stability at room temperature.
• Refrigerated storage (4°C) is recommended to ensure the stability and efficacy of cefazolin eye drop formulations.
• Further research may explore alternative formulations or preservatives to enhance room-temperature stability.