The geometric means of the parameters related with the extent of total exposure of levomethadone , i.e. , AUC ( 0-tlast ) and AUC ( 0 - ) , were 244.422 ng x h/mL and 332.999 ng x h/mL for test and 246.837 ng x h/mL and 329.467 ngh/mL for reference , respectively .