▁time . ▁Ped iat ric ▁patients ▁thus ▁have ▁a ▁larger ▁volume ▁of ▁distribution ▁than ▁adult s , ▁which ▁directly ▁affect s ▁the ▁dos ing ▁of ▁hydro ph il ic ▁dru gs ▁such ▁as ▁beta - la ct am ▁ant ib iot ics ▁like ▁am pic ill in . ▁Thus , ▁these ▁dru gs ▁are ▁admin ister ed ▁at ▁greater ▁weight - based ▁dos es ▁or ▁with ▁adjust ed ▁dos ing ▁intervals ▁in ▁children ▁to ▁account ▁for ▁this ▁key ▁difference ▁in ▁body ▁composition . ▁ ▁Inf ants ▁and ▁ne on ates ▁also ▁have ▁less ▁pl asma ▁prote ins . ▁Thus , ▁highly ▁protein - bound ▁dru gs ▁have ▁fewer ▁opportun ities ▁for ▁protein ▁binding , ▁leading ▁to ▁increased ▁distribution . ▁ ▁Met abol ism ▁ ▁D rug ▁met abol ism ▁primarily ▁occurs ▁via ▁en zym es ▁in ▁the ▁li ver ▁and ▁can ▁vary ▁according ▁to ▁which ▁specific ▁en zym es ▁are ▁affected ▁in ▁a ▁specific ▁stage ▁of ▁development . ▁Ph ase ▁I ▁and ▁Ph ase ▁II ▁en zym es ▁have ▁different ▁rates ▁of ▁m atur ation ▁and ▁development , ▁depending ▁on ▁their ▁specific ▁mechanism ▁of ▁action ▁( i . e . ▁ox id ation , ▁hydro ly s is , ▁ac et yl ation , ▁m eth yl ation , ▁etc .). ▁En zym e ▁capacity , ▁clear ance , ▁and ▁half - life ▁are ▁all ▁factors ▁that ▁contribute ▁to ▁met abol ism ▁differences ▁between ▁children ▁and ▁adult s . ▁D rug ▁met abol ism ▁can ▁even ▁differ ▁within ▁the ▁ped iat ric ▁population