HOLLYWOOD sexpot GINA GERSHON admitted she snorted cocaine – and not a substitute – while filming the  TV biopic “House of Versace”!

She dropped the bombshell while chatting with host Andy Cohen on Bravo’s “Watch What Happens Live” and left the impression that it was the real thing going up her nose.

“Gina was delib­erately going for shock value and a ‘Did she or didn’t she?’ viewer reac­tion,” according to a network insider.

“Andy’s jaw just dropped and viewers were left scratching their heads as she tried to appear coy while delivering blockbuster details from the set at the same time.”

Gina, 51, played the hard-partying fashion diva Donatella Versace, the sister of tragically murdered de­signer Gianni Versace. Donatella has admitted she was once addicted to cocaine for 18 years, and Gina didn’t hold back when a caller asked what she actually inhaled in the film.

“They tried to give me (powdered vitamin) B12, but I snorted cocaine,” the actress deadpanned.

She then high-fived fellow guest, actor Josh Gad of the Broadway hit “The Book of Mormon,” adding: “Totally not joking,” and then add­ing in a quieter tone: “Not!”

Gina continued: “No, they gave me a choice between B12 or soy milk. So I did cocaine.”

The actress is best known for her role as a bi­sexual Las Vegas stripper in the 1995 camp clas­sic “Showgirls,” and she used that role to establish herself as a lesbian icon.

“Gina knows the power of keeping her fans guessing, and she certainly knows how to work an on-camera ‘moment,’” said the insider.

“I think she deliberately used the ‘real cocaine’ anecdote to generate controversy.”