Kevin Mazur/WireImageDr. Conrad Murray has written a tell-all book about Michael Jackson — and it is reportedly explosive.

Murray, who was found guilty of involuntary manslaughter in Jackson’s death, discloses many bombshell claims about the late singer in his book titled This Is It. One of those claims is that Jackson told him he was given hormone injections at the age of 13 to retain his high-pitched voice, according to the U.K.’s The Mirror, which has been serializing the book.

“He began talking vaguely, seeming to have more difficulty describing precisely what happened to him. But what Michael said left me the impression that he had been given injections, probably hormones, to delay puberty,” writes Murray.

Murray reports being told by Jackson to swear that he would never “breathe a word” of his secret confessions, such as Michael’s alleged chronic fungal infections of his feet, which were also “were covered in callouses.” Murray writes, “The fact Michael’s feet, something critical to him, were in such poor condition was a sign not only had he neglected himself but those around him were not keeping a close eye on his wellbeing.”

The physician also writes about being the one to steer Jackson away from his use of the prescription drug Propofol, an anesthetic used before and during surgery and other medical procedures, that caused the singer’s death. “I was heavily engaged in talking to him about weaning him from the use of the [anaesthetic] Propofol,” he writes.

Murray was sentenced to four years in prison in 2011, but only served half of that term before being released in 2013.

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