Stability of a 50 mg/mL Ceftazidime Eye-Drops Formulation

Abstract

Background Microbial keratitis are severe infectionsgenerally linked to risk factors. High-doses antibiotic eye-drops could be required to avoid severe complications. In such cases, hospital pharmacists are in charge of their production given the lack of such formulations on the market. The stability of these antibiotic eye-drops is generally limited to a couple of days and publications generally do not describe addition of microbial preservatives even though it is a European Pharmacopeia requirement. The aim of this study was to describe a new ceftazidime eye-drops formulation at 50 mg/mL with a antimicrobial additive, benzalkonium chloride at 0.04 mg/mL. Methods Physico-chemical studies of this new formulation were performed by a stability indicating HPLC-UV method validated according to ICH standards, osmolality measurements, pH monitoring and visual examinations. Antimicrobial preservative efficacy was evaluated according to the method from the European Pharmacopeia. Results After 75 days at −20 °C followed by 7 days at 4 °C, or after 7 days at 4 °C, the eye-drops were stable. A degradation trend was finally observed at day 14 at 4 °C. Conclusions A new ceftazidime eye-drops formulation is proposed with a stability of 7 days. Outpatients do not need to return to the hospital pharmacy for repeat dispensing, thus possibly improving treatment compliance.

Cyclodextrins Allow the Combination of Incompatible Vancomycin and Ceftazidime into an Ophthalmic Formulation for the Treatment of Bacterial Keratitis

“…However, the formulation at pH 8 was found to be physically stable at 5 °C for at least 48 h, and this was not the case for the same formulation at pH 7.5, which is closer to the incompatibility pH limit when using HPCD. This solubility limit at 5 °C could subsequently cause storage problems since VA and especially CZ are known for being chemically instable at ambient temperatures [ 54 , 55 , 56 ]. In addition, pH 7.5 is the lowest pH that could be obtained using this formulation method for which the solubilization of CZ and VA was possible.…”