Damon Albarn took heroin "for years" whilst in recording sessions in the studio.
The Blur frontman, who claims the drug helped him to be "creative", admits he took it for a number of years during the band's height of fame and took it five days a week.
He told GQ Magazine: "I used to go to work and take heroin in the studio and then stop when I came home.
"That's why I say it's five days a week and two days off, and that's how I existed for several years."
The singer, who will release his debut solo record 'Everyday Robots' this month, also hinted he took it with Gorillaz music partner Jamie Hewlett when they were working on new music.
He explained: "We probably wouldn't have been able to create a record like that unless Jamie and I were, um, somewhat in our own worlds."
But the star insists his days of taking heroin are over and he prefers to focus simply on his music.
He added: "I still like a night out, but I certainly don't do heroin. I haven't done that for a very long time.
"Music is a compulsion with me. And God help me if I smoke any weed, I'm fucked - I'll just make more music."
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