The study was performed to compare the bioavailability of two hydroxyzine hydrochloride 25
mg tablet formulation in 16 volunteers of both sexes. The study was conducted open with randomized two
period crossover design and a two weeks wash out period. Plasma samples were obtained over a 96 h interval. Hydroxyzine concentrations were analyzed by Liquid Chromatography with Tandem Mass Spectrometry (LC-MS/MS). Bioequivalence between the products was determined by calculating 90 % confidence intervals (90 % I.C) for the ratio of AUC0-t
, AUC0-inf
and Cmax
values for the test and reference
products, using logarithmic transformed data. The 90 % confidence intervals were 81.89-105.85 %,
84.61-105.30 %, and 84.04-108.66 %, respectively. Since the 90 % confidence intervals for Cmax
, AUC0-t
and AUC0-inf were within the 80-125 % interval proposed by the Food and Drug Administration, it was
concluded that the two hydroxyzine hydrochloride formulations are bioequivalent in their rate and extent
of absorption.