Mean C ( max ) values were @ , @ , and @ ng/mL for the low - , intermediate - , and high-level coating hydrocodone ER tablet prototypes , respectively , and @ ng/mL for the hydrocodone IR/APAP tablet ; respective median t ( max ) values were @ , @ , @ , and @ h. Total systemic exposure to hydrocodone ( AUC ( @ - ) ) was comparable between hydrocodone ER tablet prototypes ( @ , @ , and @ ngh/mL , respectively ) and hydrocodone IR/APAP ( @ ngh/mL ) .