After the film screened at the Cannes Film Festival, Keith Richards of the Rolling Stones, asked director Jerry Schatzberg if he was into the hard stuff. When Schatzberg told him he wasn't, Richards asked how he could have made a film about it. Schatzberg told Richards that he could probably make a film about a woman having a baby, but, he couldn't do that either.
There is no music in this movie whatsoever.
Francis Ford Coppola showed this film to Paramount executives in order to convince them that Al Pacino was suitable for the role of Michael Corleone in The Godfather (1972).
Al Pacino's first leading role.
Was banned in the UK for four years because of its graphic depiction of drug-taking.