Billie Joe Armstrong on Rehab and His 'Gruesome' Withdrawal Period

Billie Joe Armstrong

"What the f--! I'm not f--ing Justin Bieber, you motherf--ers. You've gotta be f--ing joking."

The Green Day singer addresses his experience seeking treatment for substance abuse after his iHeartRadio festival meltdown.

Billie Joe Armstrong is opening up about the substance abuse issues that led to his onstage meltdown at the iHeartRadio festival and his experience in rehab afterward during which he suffered through a "gruesome" withdrawal period.

In the latest issue of Rolling Stone, on newsstands Friday, the Green Day singer addresses his behavior at last September's iHeartRadio fest, when he abruptly ended his set by smashing his guitar and exclaiming "I'm not f--king Justin Bieber." He said at the time he was protesting that his set was cut short by organizers; shortly thereafter, amid a torrent of media headlines about his angry rant, Armstrong was entered into a month-long outpatient rehab program for alcohol and prescription drug abuse.

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"I'm a blackout drinker. That's basically what happened [that night]," he tells Rolling Stone (via As for his problems with pills to treat anxiety and insomnia, he says: "I started combining them to a point where I didn't know what I was taking during the day and what I was taking at night. It was just this routine. My backpack sounded like a giant baby rattle."

Armstrong, 41, who's dad to two sons, Joseph and Jakob, with wife Adrienne, says he still battles "the obsession for alcohol" as well as "sleepless nights," and experienced a difficult time in withdrawal during rehab.

"That was gruesome, laying on the bathroom floor and just feeling like ... I didn't realize how much of that stuff affected me," he recalls.

After a long hiatus, Armstrong will pick up where he left off on March 10 to continue his Green Day tour in Pomona, Calif. The band recently released an album trilogy (¡Uno!, ¡Dos!, ¡Tré!), for which promotion was sidelined because of Armstrong's treatment.