Plasma concentrations of aripiprazole and the sum of aripiprazole and dehydroaripiprazole during paroxetine coadministration were 1.7-fold ( 95 % confidence intervals [ CI ] , 1.3-2 .1 , p < 0.001 ) and 1.5-fold ( 95 % CI 1.2-1 .9 , p < 0.01 ) higher than those values before the coadministration .