Resumo

Introduction: In many countries, high rates of mortality and morbidity from infectious diseases represent high social and economic costs⋅ Cefazolin sodium is a β−lactamic antimicrobial for parenteral use, belonging to the group of firt−generation caphalosporins, which stands out for its effectiveness therapeutic as well as ana agent in surgical prophylaxis, having great importance in the fight against many diseases⋅ Objective: The objective of this study was to evaluate the antimicrobial potency of cefazolin sodium when subjected to photolytic degradation, by turbidimetric bioassay⋅ Method: The parameters used were previously validated showing to be suitable for analysis of cefazolin sodium⋅ For the degradation method, the following parameters were used: 4% inoculums of Staphylococcus aureus ATCC 26923 added in BHI culture medium and aqueous solutions of cefazolin sodium in concentrations of 6⋅0, 8⋅4 and 11⋅76 μ⁄mL of cefazolin sodium⋅ The potency of antibiotic was examined by turbidimetric assay and compared with test solutions which were exposed to light UVC 254nm for a period of 1, 6, 24 and 48 hours⋅ Results: The turbidimetric analysis showed that the drug was stable in a period of 1 hour; there was no significant change in power obtained (100⋅25%)⋅ Howevwer, the degradation was evidenced by a decrease of 2⋅68%, 10⋅76% and 16⋅25% in the potency of the drug in periods of 6, 24 and 48 hours respectively⋅ Conclusions: The data show that special care in the storage and administration of the drug is necessary to maintain the quality of cefazolin sodium in dosage forms, since the drug after exposure showed considerable photolytic degradation⋅ This study contributes to knowledge of the behavior of the drug under conditions of stress, indicating improvements in the qulity of the drug to ensure its therapeutic efficacy⋅