The drug -- also known by the brand name Diprivan -- is most often used to sedate patients before a medical procedure, but it is also one that palliative care workers have been known to administer to terminal patients who are in pain or who have weeks or days to live.
Lee said during a call from a Jackson staffer she heard Jackson in the background requesting the sedative.
"He said, 'Find me an anesthesiologist. I don't care how much money they want. find me an anesthesiologist to be with me here overnight and give me this IV,'" she said.
Jackson, Lee said, said he was in extreme discomfort, was desperate for sleep and said that one side of his body was hot and the other side cold.
Lee said she wasn't familiar with the drug when he first asked for it three months ago, but after consulting with a doctor, she warned Jackson it could kill him.
"'I look at you Michael and I've been around you long enough now, I love you as family. I would not give this to anyone,'" Lee said she told Jackson. "I said, 'This is not a safe medicine, please don't take this.'"
Pain specialists told ABC News that home use of the risky drug would be highly unusual, since it's ordinarily given in a hospital setting due to its health risks. Obtaining propofol with a simple prescription is next to impossible.
"Propofol has no place in a household," said Dr. Lloyd Saberski, a Yale University anesthesiologist and editor in chief of the journal The Pain Clinic. "This alone is a deviation, and many laws were likely violated just to get the propofol there."
Moreover, an injection of the drug requires that someone be present to continually administer it intravenously, said Dr. Howard Nearman, chairman of the anesthesiology department at University Hospitals Case Medical Center in Cleveland.
Nearman said there "absolutely" had to be a second party with Jackson if indeed he was using the drug to sleep.
Whether or not propofol was in Jackson's system at the time of his death will only be answered with the release of the pop star's autopsy results, which the Los Angeles County coroner's office has said will take weeks.
The potency of Propofol as an anesthetic is widely known; in anesthesiology circles, the drug, a white liquid, is termed "milk of amnesia" by some.
"Propofol is an agent that requires very close monitoring and is often limited only to use by anesthesiologists," said Dr. Richard Page, head of cardiology at the University of Washington medical center. "The main issue with this agent is respiratory depression, which in turn could cause cardiac arrest."
"It is a very dangerous drug," said Dr. Brian Olshansky, a cardiologist at the University of Iowa who said he often uses the drug to place patients in deep sedation for certain heart procedures. "It is not for sleep. I cannot imagine anyone would use this outside a very regulated environment such as the availability of emergency respiratory equipment."
One main reason for this, he said, is the speed with which the drug has its effect.
"It rapidly induces unconsciousness and apnea," Olshansky said. "People stop breathing within seconds of being given the drug."