The guitarist has revealed that he entered rehab whilst The Strokes were working on their new album 'Angles'.

The drug substance was not named but the band said that Hammond Jr's drug problem became dangerous when he suffered 'a stroke' in 2009.

"We all saw something was broken - certain people getting into drugs. There was a lot of nodding off and passing out in the studio, like, 'Jesus, you're not awake to record your part, we have to wait four hours so you can nap," guitarist Nick Valensi told Spin.

In the interview, Hammond Jr described his time in rehab and admitted that he 'wasn't really there' when the band started recording 'Angles'.

"I wasn't on any chemicals. It was hard - you have two good years of post-acute withdrawal. I was nervous and couldn't remember things. It's like having a stroke, no pun intended. You always do the crazy rock star thing, of course, but I'd rather be left with music from someone I admire than their funny stories of all the f*cked-up s*it they did."

The Strokes have revealed that they will start work on their next album in April.

(by Holly Frith)