Intense anxiety before a TV interview once made Oscar-winner Joaquin Phoenix throw up backstage.

The "Joker" actor has shared the experience with GQ magazine, adding that has to take special measures to cope with his stress when working, reports aceshowbiz.com.

Phoenix said he "still gets crippling anxiety for weeks before shooting starts" and "feels physically sick" when he begins working on new projects.

"For the first three weeks of shooting, I sweat so much that they have to put pads in my armpits."

Film director James Gray told the portal: "He is incredibly shy - something most people think is an act or something."

Gray, who worked with Phoenix on projects like "We Own the Night" and "The Immigrant", recalled once waiting backstage with him before a TV interview, when he got so nervous he puked.

He didn't share what show the star was due to appear on.

Phoenix said his nerves come about because "everything they teach you as a kid (about acting) is completely f**king wrong."

"They teach you to remember your lines. Wrong! They teach you to follow your light. Wrong! They teach you to hit your mark. Wrong, wrong, wrong! Those are the things that you shouldn't do."