ENHANCED SUSCEPTIBILITY OF ESCHERICHIA COLI, STAPHYLOCOCCUS AUREUS AND STREPTOCOCCUS PYOGENES TO FLUOROQUINOLONES IN THE PRESENCE OF PROCHLORPERAZINE
Combating the problem of microbial resistance is one of the major challenges the medical sciences facing today. Inhibition of resistance mechanism in bacteria seems much better approach than developing new antibiotics only. The present study was aimed to investigate the effect of different concentrations of prochlorperazine in increasing the effectiveness of fluoroquinolones against Escherichia coli, Staphylococcus aureus and Streptococcus pyogenes. The bacteria were isolated from indigenous sources and identified through cultural characteristics, Grams’ staining and biochemical tests. The master suspensions were subjected to viable count and inoculated at the rate of 106 CFU/ml of the media for antimicrobial sensitivity testing. The four fluoroquinolones i.e. ciprofloxacin, levofloxacin, pefloxacin and norfloxacin were first applied to bacterial cultures alone and then in combination with four different concentrations (16μg/ml, 32μg/ml, 64μg/ml and 128μg/ml) of prochlorperazine and inhibition of growth was recorded in terms of diameter of zones of inhibition. A linear relationship was found between the increase in concentration of prochlorperazine and diameter of zones of inhibition against all the fluoroquinolones. The diameter of zones of inhibition were significantly (p<0.05) greater with 128μg/ml of prochlorperazine in combination with all the four fluoroquinolones against Staphylococcus aureus and Streptococcus pyogenes. In contrast E. coli showed significant susceptibility (p<0.05) only to ciprofloxacin and norfloxacin in the presence of prochlorperazine. It was concluded that prochlorperazine is capable of increasing the susceptibility of Staphylococcus aureus, Streptococcus pyogenes and E coli when used in combination with different fluoroquinolones. This approach of hindering the resistance mechanism of bacteria with non-antibiotics can shift many of the resistant strains of bacteria to susceptible.