He underwent 27 surgeries over the course of four months, waking up in the middle of some of them.
"You're so prone to infection," he told Access Hollywood Live. "I had, like, 65 per cent of my body was basically burned or, like, an open wound, so every couple of days they would scrub you ... It was the worst.
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"And then my medication wasn't right, because I was self-medicating so much before the accident that I'd wake up during surgeries. It was such a painful experience.
"I think it took them a while to figure out like, 'OK, this guy was a drug addict, and that's the reason none of these medications are working'."
It was a time of deep depression for Barker, who wasn't allowed visitors because they posed a risk of infection.
"It was, like, a living nightmare," he said.
- AAP