Linday Lohan's first overdose came when she was 18: Report

Lindsay Lohan was 18 years old when she had her first cocaine overdose, and she's been battling alcohol and drug addiction for more than 10 years.

That's according to dad Michael Lohan, who dished to British newspaper The Sun about LiLo's alleged first overdose, saying he planned to kill the assistant who gave Linz the coke.

"Lindsay was filming in New Orleans and I got a call saying she had overdosed on cocaine. One of her assistants had given her the drug," Michael told The Sun of the alleged 2005 incident.

"I was so angry I got a gun from the house and planned to go to New Orleans to kill him."

Michael, 53, gave the paper a sprawling interview, in which he said he thinks LiLo's career is over if she doesn't clean up her act and that the floundering star is now addicted to vodka and Adderall.

"If Lindsay does relapse, then I think it will be over for her with Hollywood," he said. "There will be no more second or third chances. She has got to stay clean and sober this time."

Lohan, 27, will wrap up her 90-day stint in rehab at the end of this month for lying to cops about a California car wreck, and she reportedly plans to move to New York to live with mom Dina.