scag
Addict's white powder
Scag is slang for heroin, used since the mid-20th century among drug users and in crime contexts: He was strung out on scag.
The term appears frequently in gritty urban narratives and police dramas.
In British slang, scag can also mean a cigarette or, as a verb, to damage or scratch something.
junk
Worthless discarded items
needle · overdose · addiction · withdrawal · dealer · street · cut · spike · vein · nod
snag
Unforeseen complication
thread · catch · flaw · damage · loop · knit · weave · sweater · hosiery · defect
legality/legitimacy
Medicine requiring medical authorization
pharmaceuticals · medicine · over-the-counter drugs · aspirin · vitamins
sobriety/intoxication
scagsobriety
Unimpaired mental state
clean · sober · straight · clearheaded · abstinence