Charlie Sheen will be the first to tell you: He's on a drug called Charlie Sheen.
What does that even mean? No one is sure, but the actor began a public rampage and media frenzy in 2011 that leaves many wondering if Sheen is fueled by substance abuse, mental illness or a bit of both. He has a long history of erratic, angry and violent behavior and a well-documented history of drug abuse. During his current ongoing meltdown, he denies he's using drugs or alcohol and has passed supervised mandatory drug tests. He dodges questions about mental illness and whether he has bipolar disorder, but continues to tell it like he sees it, whether you like it or not.