Insiders claim that the 19-year-old singer has significantly increased his consumption of marijuana and "lean" or "sizzurp" (prescription cough syrup mixed with soda and a jolly rancher), adding that he is "constantly high" and rarely leaves the house.
"[Bieber's been] drinking more lean, smoking more weed than ever," one source said.
What's more, the singer has been reportedly pushing away everyone who has "ratted" him over his drug use. TMZ adds that while Bieber does spend a lot of time working in the studio in Atlanta, he is rarely sober during his jam sessions.
Reports of the singer's alleged drug abuse come two days after police found marijuana in an Escalade that was seized at the singer's home by local authorities, and two months after he was arrested in Miami for driving under the influence, drag racing, driving with an expired license and resisting arrest without violence.
Bieber's downward spiral could reach rock bottom soon. He is expected to go to trial over his January arrest, after he reportedly rejected a plea deal offered by Miami prosecutors because he didn't want to submit himself to random drug testing.