Green’s Dictionary of Slang

hero (of the underworld) n.

also heroina

(drugs) heroin.

[US]Anslinger & Tompkins Traffic In Narcotics 310: hero. Heroin.
[US]E.E. Landy Underground Dict. (1972).
[US]ONDCP Street Terms 11: Hero — Heroin; Hero of the underworld — Heroin. Heroina (Spanish) — Heroin.