The former child star recently opened up to Life & Style magazine about her forthcoming tell-all memoir, titled "Melissa Explained It All," where she reveals her history of drug use.
"I experimented with weed, Ecstasy, mushrooms, and mescaline for about a year and a half," she said.
According to omg! Insider, Hart also dished to the mag about her past flings with Hollywood studs like Jerry O'Connell and Backstreet Boys' Nick Carter.
But there was one particular celeb, Ashton Kutcher, who couldn't steal her heart -- she kicked him out of parties multiple times for making rude remarks.
Read more about Hart's story when "Melissa Explained It All" releases Oct. 29.