The 90 % CI of geometric mean ratios ( sildenafil granule/tablet ) for the pharmacokinetic parameters of sildenafil were within 0.8 1.25 , as a bioequivalent acceptable range ; 1.111 ( 90 % CI , 1.002 - 1.231 ) for maximum plasma concentration ( Cmax ) and 1.092 ( 1.019 - 1.117 ) for area under the concentration - time curve from time zero to time of last measurable concentration ( AUClast ) .