Pop star Justin Bieber has reportedly become increasingly dependent on steroids which has caused his recent bizarre behaviour.
According to The Sun the 19-year-old has been using Clenbuterol, a diet drug which is most commonly used on the horses.
The claims come after the singer emerged from his Miami rental on Friday evening following his DUI arrest.
The paper reports that Justin, who is currently on bail, started using the drug after he discovered weight lifters use it to gain extra muscle definition.
A source said: 'As well as drinking and smoking weed, Justin's been taking steroids to give himself a six pack.
'His physique had gone from boy-like to muscled in a very short time and his mood have become wildly erratic.'
The singer appeared in high spirits when he left his Miami mansion to hundreds of waiting fans on Friday evening.
His appearance followed a tweet just a few hours earlier in which Justin finally addressed his fans telling them to stay strong as criticism is leveled at their support following the incident - that involved drugs, alcohol and drag racing.
The young star has however, refused to comply with his management team that has urged him to check into rehab.
The teen instead is thought to be spending time with his father, who was not only said to be on the scene with Justin when he entered a drag race with rapper Khalil Sharief, aged 19, in Miami Beach that resulted in the teen going 'up to 60 mph' in a 30 mph zone, according to Miami police.
But the dad was also apparently partying with him at SET nightclub just hours earlier, where Justin was already high - he had told police during the time of his arrest that he had smoked marijuana 'all day,' was on prescription drugs and had consumed a beer.
However after his son's arrest his father tweeted about 'the lies of the enemy' writing that 'I can protect my kids but I can't protext them from you and your lies.'
Noticeably absent in this episode of Justin's life is the woman who raised him pretty much all by herself, Pattie Mallette who has yet to comment on her son's arrest.
The frequent tweeter has not typed a word since Wednesday, the day before the arrest.
Her name was brought up by TMZ that reported Bieber told Miami police his mother had given him the anti-anxiety prescription medication Xanax.
A spokesperson for Justin has declined to comment.
- Daily Mail