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.