tokens: Mean disposition constants ( + / - SD ) were obtained from individualized fits ( V1 : 0 . 398 + / - 0 . 336 LITER / KG , Vdarea : 2 . 53 + / - 0 . 72 liter / kg , alpha : 0 . 316 + / - 0 . 294 min - 1 , beta : 0 . 00204 + / - 0 . 00262 min - 1 , k2 : 0 . 0305 + / - 0 . 0101 min - 1 ) .