"When my father was going public, that's when I hit rock bottom," Fox News quoted her as telling The Sun.
She added: "I tried to mask my problems with alcohol, cocaine and mind-altering substances. I ran myself down and lost track of who I was."
Recollecting her May 2007 arrest for DUI (driving under the influence) and possession of cocaine, she said: "I just thank God everyone was okay. But it was scary. I had three drinks, at most. I've been stupid and childish and I wasn't thinking."
Lohan insists she has now got rid of her addiction.
She said: "I've made some dreadful mistakes but learned from them - that has probably saved my life.
"Mind-altering drugs are so dangerous. I'm allowed to drink now but I know my limits. Partying so hard isn't worth it."