Justin Bieber has spoken candidly about his drug use and revealed he feared it would kill him.

Speaking in the latest episode of his YouTube series Justin Bieber: Seasons, the singer said he moved on to harder drugs as he struggled with the pressure of being one of the world's most famous musicians.

Bieber said the drugs were an "escape", adding: "I was young, like everybody in the industry and people in the world who experiment and do normal, growing up things.

"But my experience was in front of cameras and I had a different level of exposure. I had a lot of money and a lot of things."

He said he decided to get clean because he feared the drug use was about to kill him and admits members of his security team would check his pulse throughout the night to make sure he was still breathing.

"People don't know how serious it got," he said. "It was legit crazy scary.

"I was waking up in the morning and the first thing I was doing is popping pills and smoking a blunt and starting my day. So it just got scary."

 Justin Bieber and Hailey Bieber attend the premiere of YouTube Originals' 'Justin Bieber: Seasons' at Regency Bruin Theatre on January 27, 2020 in Los Angeles, California. 

Bieber infamously had several brushes with the law, including allegations of vandalism, assault and driving under the influence.

In 2014 his smiling mugshot following an arrest for drink driving in Miami, Florida, went viral.

In the documentary series, Bieber blamed his behaviour on his upbringing.

"I started valuing the wrong things in this business, because there was things dangling in front of me," he said.

"If I get this, I'll be happy. If I do this, I'll be happy."

"These are things that I think a lot of people with secure households learn at a young age."

"I never had that security in a family. I never had that consistency. I never had the reliability and the accountability."

Bieber added: "My parents never gave me those tools to be a good team player."

The singer's wife, model Hailey Bieber, also appears in the documentary and said she chose not to get involved in his life until he "chose to get sober".

The couple married in secret in New York last September.

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