Norfloxacin Case Study

DISCUSSION An interaction might occur when two or more agents are taken together. The likelihood of these interactions increases when herbs or herbal products are involved due to their multicomponent nature. The clinical result of such an interaction will likely affect therapeutic outcome either positively or negatively. Meanwhile, effective microbial control of urinary tract infection depends on the excretion and sustenance of therapeutic concentration of antimicrobial agents in urine. The excretion rate data revealed that the herbs significantly reduced the elimination of norfloxacin, with the effect of tea being higher than that of GKS. This interaction may not be attributed to partition coefficient because our preliminary unpublished
This follows since the RUIT of norfloxacin reveal that the highest bacteriostatic potency in urine was attained in subjects that consumed the antibiotics concurrently with tea. In contrast, the excretion rate data shows that tea reduces urinary excretion of norfloxacin. The TDmax of 3.0 is consistent with the peak RUIT (3.0 h). This suggests that the tea constituents may have enhanced the sensitivity of the infecting organism (E. coli) to norfloxacin, or acted synergistically or additively against E. coli, or involved both mechanisms. Possible additive or synergistic antibacterial effect at the 1st and 3rd hour may be associated with the antimicrobial catechins present in tea, which are principally excreted in large quantities in urine at these periods (Fung et al., 2013; Lee et al., 1995). Previous studies reported a urinary excretion of tea metabolites between 8.1 % to 28.5 % of intake (Clifford et al., 2013). Herbal products can enhance or reduce the sensitivity of microorganisms (Smirnova et al., 2012). It is also likely that the extended antimicrobial activity shown by GKS was due to the antimicrobial principles from GKS which were excreted (Seanego and Ndip,
This study shows that tea increased antibacterial activity of norfloxacin. A previous in vitro study demonstrated that the constituents of tea are indifferent to the antimicrobial effect of ciprofloxacin while it enhances that of tetracycline (Ahmad and Aqil, 2007). Since tea extracts possess antimicrobial property, it may be that the synergy with norfloxacin results from catechins and its conjugates excreted unchanged in urine (Reygaert and Jusufi, 2013). This is similar to the interaction of the quinolones with milk. While gastrointestinal absorption of ciprofloxacin is affected by dairy product (Pápai et al., 2010), norfloxacin is not affected (Lehto and Kivistö,