The 25-year-old singer - who is known for her love of musical theatrics - admits she spent a lot of time trying to find herself by doing drugs, and only stopped when her father caught her out.
Speaking in an interview with designer Jean Paul Gaultier, she said: "I just was partying and being very self-indulgent and trying to find myself. In hindsight, it`s so dangerous and I don`t encourage anyone to follow that path.
"I remember my dad, I was actually doing drugs in my parents` house one day and they didn`t know I was in the bathroom. I came out and my father could tell, and I just remember feeling so embarrassed and I quit instantly."
"I care so much about my father, I`m very Italian American about those things. It was pretty instant."
Now the `Judas` hitmaker relies on her fans - known as Little Monsters - to provide her with a better high than drugs could.
She added: "What I`ve come to realise about my life is the joy and euphoria I experience with my fans is far better than drugs could ever be."