I read that Diprivan doesn't stay in the system very long. The LA Times article mentioned more side effects of the drug. So far they've found only prescription bottles, some unmarked, not the intravenous supplies necessary to administer the drug.
Clip:
The Los Angeles Times is now reporting that investigators are focusing on at least five doctors who prescribed drugs to Michael Jackson.
...A lawyer for Dr. Conrad Murray, Jackson's personal physician, said the doctor had prescribed neither OxyContin nor Demerol to the pop icon. He has not commented on Diprivan.
Five Jackson Docs Reportedly Investigated
Investigators focus on five Jackson doctors - Los Angeles Times