Michael Jackson's Personal Physician  was with him when he went died.

Reports are in circulation that 45 minutes before his Cardiac Arrest, he took or was administered Demerol, which can cause "Hazardous use, harmful use, dependence, and diversion"

"Demerol is a fast-acting opioid analgesic drug. In the United States and Canada, it is more commonly known as meperidine or by its brand name Demerol. Pethidine is indicated for the treatment of moderate to severe pain. Compared to morphine, pethidine was supposed to be safer and carry less risk of addiction." Wikipedia.

According to Wikipedia "Michael Jackson, throughout the later years of his life, was rumored in the media to be continuing the use of Demerol. Jackson was first linked to using Demerol after a burning incident on set, while filming a 1984 Pepsi commercial"

If Michael Jackson has been using the drug since 1984, as it states here, then  25 years of use might just have been the trigger,. as opposed to any one particular dosage, ie. the one yesterday.

Preliminary Autopsy report is expected in the next few minutes

Watch Live Breaking News from Sky News of Michael Jackson's Shock Death