As previously reported by AccessHollywood.com, officials are in the process of reconstructing the King of Pop's medical history following his death on June 25. Toxicology results from his subsequent autopsy are still several weeks away and Michael's cause of death has been deferred.
A source told the Times on Wednesday that "any and all" Jackson medical records had been subpoenaed, "including radiology and psychiatric records."
An attorney for Dr. Arnold Klein, Michael's friend and dermatologist, confirmed to the newspaper that the doctor had received a subpoena.
The Times previously reported that at least three doctors were part of the investigation. According to the newspaper's sources, such an investigation could be necessary to determine the star's cause of death. A drug such as the anesthetic Diprivan, reportedly found in Michael's Holmby Hills home, goes through the body quickly and thus might not appear in toxicology tests.
Anesthesiologist Paul Wischmeyer told the newspaper that Diprivan would be "probably undetectable" in the bloodstream 20 minutes after a dosage, but that alternate tests could be done to look for evidence of the drug.
"You can find it in the urine," he said. "It wouldn't be a test a coroner could do, but they could send out for it."
Dr. Klein appeared on CNN's "Larry King Live" on Wednesday, where he told Larry that he had prescribed Michael the painkiller Demerol, but had warned him about Diprivan.
"I told him he was absolutely insane," Klein said, having allegedly discovered that the singer was using the drug while on tour in Germany.
He defended his own prescriptions to Michael, adding, "If you took all the pills I had given him in the last year at once, it wouldn't do anything to you."
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PLAY IT NOW: Michael Jackson's Dermatologist, Arnie Klein, Speaks Out (July 8, 2009)