HPLC method development, validation and its application to investigate in vitro effect of pioglitazone on the availability of H1 receptor antagonists

The method has been developed and validated for the simultaneous determination of pioglitazone and H1-receptor antagonists (fexofenadine, cetirizine and levocetirizine) in formulations and human serum. Utilizing HPLC techniques, an assay was designed to determine the in vitro effects of pioglitazone on H1-receptor antagonists. Obtained results were verified using the UV spectrophotometric technique. First-derivative values versus concentrations were used to plot calibration curves of these drugs and were found to similar with the HPLC data. The availability of pioglitazone remained unchanged in absence or presence of fexofenadine, cetirizine and levocetirizine. This in vitro analysis confirms the harmless co-administration of pioglitazone and H1-receptor antagonists, and can serve as the foundation for designing further in vivo studies.