In Vitro Drug Interaction Studies Between Ciprofloxacin and Selected Herbal Preparations Commonly Co-administered in Bauchi State

Concurrent use of conventional antibiotics with herbal preparations is a common practice in North East Nigeria, particularly in Bauchi State, where herbal medicine is deeply integrated into health-seeking behaviour. Potential pharmacokinetic interactions at the level of drug absorption and plasma protein binding represent a safety concern, especially for fluoroquinolone antibiotics like ciprofloxacin. This study investigated in vitro interactions between ciprofloxacin and aqueous extracts of three herbal preparations commonly co-administered in Bauchi State: Parkia biglobosa pod extract, Tamarindus indica fruit extract, and Moringa oleifera leaf extract. Interaction was assessed by equilibrium dialysis for plasma protein binding displacement and UV-spectrophotometric chelation studies to assess divalent cation-mediated complexation. All three herbal extracts reduced the UV absorbance of ciprofloxacin in solution, suggesting potential complexation. Dialysis studies showed that Parkia biglobosa extract displaced ciprofloxacin from plasma proteins by 18%, potentially increasing free drug concentration. T. indica extract reduced ciprofloxacin dialysis by 22%, suggesting reduced bioavailability attributable to its high tannin content. These preliminary in vitro findings indicate potential pharmacokinetic interactions warranting further in vivo investigation. Healthcare providers and pharmacists in Bauchi should counsel patients against unsupervised concurrent use of these herbal preparations with ciprofloxacin. Keywords: ciprofloxacin, herb-drug interactions, Bauchi State, protein binding, in vitro.