Justin Bieber off Sizzurp

Troubled singer Justin Bieber is reportedly off Sizzurp after months of downing in the codeine cocktail.

Sizzurp, also known as 'purple drank', is made from prescription cough syrup, hard candy and sugary soft drinks, and is popular among rap stars like Bieber.

Sources close to him said that he's been clean for a month, largely because he's become obsessed with working out and it's just really hard to do when you're high, reports tmz.com.

Apparently, it's no coincidence that Bieber has been spending more time with Scooter Braun and his mom over the last month ... he kept his distance during his Sizzurp binges.

Detoxing from Sizzurp isn't easy, especially when you use it all the time. You'll recall ... during the Sheriff's search of Bieber's Calabasas home, deputies found four or five empty codeine bottles and various styrofoam double cups.