In vitro drug interaction studies of fexofenadine with enoxacin, levofloxacin and sparfloxacin

An in vitro availability of fexofenadine in the presence of quinolones (enoxacin, levofloxacin and sparfloxacin) was carried out on a BP 2005 dissolution test apparatus. Fexofenadine second generation non sedative H1 receptor antagonist is an active carboxylic acid metabolite of terfenadine. These reactions were performed at different pH environment (2, 4, 7.4 and 9) at 37 oC human physiological temperature, at 48 and 60oC. By the alteration of Beer's law through simultaneous equation of two components system the reactions were studied. The ultraviolet method is simple and quite accurate. The results from interaction and kinetic studies reveal that these drug interactions are not temperature dependant, but pH dependant and occur more frequently in more acidic or basic medium.