Cherilyn Lee told how she went to Jackson's home on April 19, when the singer asked her to treat him with propofol by intravenous (IV) drip because other treatments were not working.
"He told me, 'doctors have told me that it's safe, I just need to be monitored'," she told the Los Angeles Superior Court.
"'I just need somebody to come here, I will be safe ... as long as I am being monitored'," she quoted him as saying, adding that she refused to treat him with the drug after learning it was a surgical anaesthetic.
Murray, 58, told police that he had been treating Jackson with propofol via IV for two months, but had started to wean him off three days before his death.
In a police interview played earlier during the five-week trial, Murray told how he tried to get Jackson to sleep from around 1am, but failed and finally gave him 25mg of propofol at 10.40am.
At some point after that, he said, he left for two minutes to go to the bathroom, and returned to the bedroom to find Jackson not breathing.
Cherilyn Lee said the singer told her on April 19 that he knew about propofol because he had been given it as an anaesthetic for surgery in the past.
"'I want to be able to fall asleep easily so that I can get enough rest because I'm in the midst of doing a lot of work right now ... as soon as it gets into my vein I'm knocked out and I'm asleep'," she quoted him as saying.
The testimony came after Jackson's brother Jermaine confirmed on Twitter that the singer had suffered from insomnia for years, as Jackson's long-time doctor Allan Metzger has told the court.
"Dr Metzger confirmed what I've said all along: Michael's insomnia was historic & tour/pressure induced," and nothing to do with Demerol, a drug Jackson was reportedly given by a dermatologist, he tweeted on Monday.
He said Jackson had "trouble sleeping in Feb 2009 because he'd been preparing for TII [This is It] since Fall 2008. that's when pressure started to grow.
"Many artists unable to turn off mind will empathise with this insomnia. Michael slept okay when not performing. In bed around 9pm ... and slept," Jermaine Jackson added.
In other developments, the trial judge yesterday banned defence lawyers from asking about Jackson's multimillion-dollar contract for his concert series.
"This is not a contractual dispute, this is a homicide case. We are not going to get into accounting and going into a host of other materials that distract from the case," said judge Michael Pastor. AAP
