Influence of Sanguisorba officinalis, a mineral-rich plant drug, on the pharmacokinetics of ciprofloxacin in the rat

The significance of an interaction between ciprofloxacin and Sanguisorba officinalis L. (SO), a mineral-rich herbal medicine, was evaluated in this study. Male Sprague-Dawley rats (220-250 g) receiving ciprofloxacin dosages of 20 mg/kg po were concomitantly dosed with an aqueous extract of SO (equivalent to 2 g/kg crude drug). Blood and urine samples were collected over 6 and 24 h, respectively, for the quantitation of ciprofloxacin by HPLC. The presence of SO reduced significantly (P < 0.05) the maximum plasma concentration, the area under the concentration-time curve and the urinary recovery of ciprofloxacin, by 94%, 78% and 79%, respectively, compared with rats receiving only ciprofloxacin. The presence of SO also caused an eight-fold and two-fold increase in drug distribution (Vd, lambda(z)/F) and terminal elimination half-life (t1/2, lambda(z)) from 30.8 L/kg and 1.96 h, respectively. Therefore, should the use of both agents be required, sufficient time should be allowed to ensure the efficacy of ciprofloxacin.