Background Ceftazidime is used for the treatment of endophthalmitis by intravitreal injection. For this emergency treatment, the syringes must be available immediately in the pharmacy. The stability at 2–8°C is limited and does not allow batch production.

Purpose To study the stability of ready-to-use ceftazidime solution at 20 mg/mL in 0.9% sodium chloride in polypropylene syringes after storage at −20°C, to allow preparation in advance.

Materials and Methods We used the High Performance Liquid Chromatography method published by Abdel Hamid ME et al, Farmaco 1998; 53: 132–138.

The analytical conditions were: Column C18 5µ 200 × 4.6 mm. Mobile phase (ammonium acetate buffer 0.1 M pH 7.5/acetonitrile 90/10), flow rate: 1 mL/mn, wavelength: 256 nm.

The HPLC method was validated according to ICH guidelines (linearity, repeatability, stability-indicating capability).

Syringes were stored at −20°C and 4°C to compare with the literature data.

Results Stability was defined according to ICH guideline Q1A: above 95% of the initial concentration of ceftazidime and concentration of degradation products less than 2%. After storage at 4°C, the ceftazidime concentration fell under 90% after 3 weeks and there was 65% of the initial concentration after 90 days.

The ceftazidime solution at 20 mg/mL was stable for 3 months at −20°C with more than 96% of the initial concentration and degradation products under 0.8%.

Conclusions Ceftazidime 20 mg/mL in 0.9% sodium chloride was stable for 3 months at −20°C. This allows batch preparation in advance and the immediate availability of the syringes to treat patients.

No conflict of interest.