The actor suffered a highly public meltdown and was fired from his sitcom Two and a Half Men in 2011 following a nasty feud with show bosses.
Sheen's bizarre antics became headline news and he appeared to capitalise on his notoriety by setting off on a comedy tour of the US and Canada, called My Violent Torpedo Of Truth/Death Is Not An Option.
However, many of the shows were met with mixed reviews from audiences, and some disastrous gigs ended in walkouts and heckling.
Sheen, who was one of America's best-paid TV actors during his time on Two and a Half Men, has now explained he only set off on the tour because he needed the money after he lost his job.
He told Piers Morgan on a US TV show: "It was brutal. I was not winning at all. I think what a lot of people don't realise is I was completely broke, because, you know, when they kept my back end and fired me and all that, I didn't have any money left.
"So I was using the tour to actually pay child support and mortgages and stuff like that. You know? So I'm grateful for that."
Sheen went on to admit he wanted to cancel the tour when gig-goers in Detroit, Michigan began hurling missiles at the stage and walking out, but he was determined to fulfil his commitments.
He added: "It was in Detroit... that was bad... Detroit was bad... (I was) dodging stuff. Literally dodging stuff.
"The forward momentum of it kind of lost its lustre after about show seven. And I knew I had 15 or 14 left... I didn't have an act. There was no act.
"I think people were expecting to show up and literally watch me die on stage or spontaneously combust or just like suddenly become cash and women. I don't know what they were expecting.
"That's when I had to dig deeper and keep going, keep moving forward, because I gave this company my word that I would finish this. And I did, against all odds."