The actors snorted crushed B vitamins for scenes that involved cocaine. Jonah Hill claimed that he eventually became sick with bronchitis after so much inhaling and had to be hospitalized.
Matthew McConaughey's scenes were shot on the second week of filming. The chest beating and humming performed by him was improvised and a warm-up rite that he performs before acting. When Leonardo DiCaprio saw it while filming, the brief shot of him looking away uneasily from the camera was him looking at Martin Scorsese for approval. DiCaprio encouraged them to include it in their scene and later claimed it "set the tone" for the rest of the film.
Wanting to work with Martin Scorsese, Jonah Hill took a pay cut by being paid the S.A.G. minimum, which was $60,000.
Originally, Martin Scorsese offered Margot Robbie to appear wearing a bathrobe during the seduction scene between her and Leonardo DiCaprio. Robbie refused and insisted on doing the scene fully nude, her first in her career. According to Robbie: "The whole point of Naomi is that her body is her only form of currency in this world...She has to be naked. She's laying her cards on the table." Robbie said she had three shots of tequila in succession before shooting the scene to relax because she was "very, very nervous." After shooting was complete, Robbie initially fibbed to her family and friends about doing the nude scene in order to delay any personal repercussions, claiming CGI was used to superimpose her head on a body double. She eventually changed her mind and confessed when the film was released.
Martin Scorsese: the voice of John, the first client, to whom Jordan sells Aerotyne I.N.D. penny stocks.