▁ing red ient ▁which ▁results ▁in ▁a ▁lower ▁peak ▁concentration ▁in ▁blood ▁pl asma . ▁ ▁Chem istry ▁ ▁Its ▁structure ▁incorpor ates ▁the ▁back bone ▁of ▁am ph et am ine , ▁the ▁pro tot yp ical ▁C NS ▁stim ul ant ▁which , ▁like ▁phen met raz ine , ▁is ▁a ▁re le asing ▁agent ▁of ▁dop am ine ▁and ▁n ore pine phr ine . ▁The ▁mole c ule ▁also ▁lo os ely ▁res emb les ▁eth c ath in one , ▁the ▁active ▁met abol ite ▁of ▁popular ▁an ore ctic ▁am fe pr am one ▁( di eth yl prop ion ). ▁Un like ▁phen met raz ine , ▁eth c ath in one ▁( and ▁therefore ▁am fe pr am one ▁as ▁well ) ▁are ▁mostly ▁select ive ▁as ▁nor ad ren al ine ▁re le asing ▁agents . ▁ ▁Rec re ational ▁use ▁ ▁Ph en met raz ine ▁has ▁been ▁used ▁recre ation ally ▁in ▁many ▁countries , ▁including ▁Sweden . ▁When ▁stim ul ant ▁use ▁first ▁became ▁pre val ent ▁in ▁Sweden ▁in ▁the ▁ 1 9 5 0 s , ▁phen met raz ine ▁was ▁preferred ▁to ▁am ph et am ine ▁and ▁m eth am ph et am ine ▁by ▁users . ▁In ▁the ▁aut obi ographical ▁novel ▁R ush ▁by ▁Kim ▁W oz enc raft , ▁int ra ven ous ▁phen met raz ine ▁is ▁described ▁as ▁the ▁most ▁eu ph or ic ▁and ▁pro - sex ual ▁of ▁the ▁stim