- Health Care, Drugs & Insurance
Propofol (Diprivan), what is it and how does it work?
Propofol - Diprivan
What is Propofol? (also known by the brand name Diprivan).
Propofol is a drug used to induce near instantaneous sleep (hypnotic) for both major and minor surguries. It is also used by Veteranary sciences for anesthetizing animals.
Propofol is approved for use in fifty (50) different countries and is also available in generic form.
What is it?
Propofol was first marketed by Imperial Chemical Industries (now Astra-Zenica) in 1977 as a drug called Cremophor EL. Unfortunately, there were too many anaphylactic reactions with Cremaphor and the drug was pulled from the market. Shortly after ICI re-marketed the drug in a soy oil/water emulsion (99%) with the active ingredient taking up only 1% of the total volume.
Due to the high volume of oil (10%) and water (89%), the oil's total emulsion in the solution causes the liquid looks like milk.
Health care professionals who use this preparation jokingly refer to it as "milk of amnesia."
How does it Work?
Propofol binds to GABAA receptors in the central nervous system. These receptors, once blocked, are known to cause a reduction in anxiety and also induce sleep. Propofol is known to bind to these sites and in sufficient quantities can induce a dreamless, near coma-like state in those given the drug.
Like many drugs Propfol is cleared from the body by the liver. However, since it is known that Propofol's effects are reduced or eliminated within minutes of cessation of administration and a close study reveals that it's impossible for the liver alone to eliminate that much of the drug, it is also thought that the drug is taken up by surrounding tissues such as vein walls, muscles, and fatty tissue. Once a drip of the drug has stopped patients can re-awaken in as little as two minutes and be fully aware and able to drive or resume work activities within a short period of time (one to three hours for most).
Propofol can be administered for very short or long durations depending on the procedure it is needed for. From minutes to hours.
For these reasons this is a very popular anesthetic.
How many Deaths can be traced to Propofol?
Beside the death* of Michael Jackson, there have been only three deaths (possibly four) recorded, all but one related to the abuse of the drug. In all but one case the deaths were of medical professionals attempting to use the drug in a non-medical setting (such as the home).
In one other case Oliver Travis O'Quinn, a registered nurse who fled to Ireland, is suspected of murdering Michelle Herndon, a student he was obsessed with, by injecting her with four times the normal dosage of propofol required to anesthetize a person her size and weight. It is almost certain that propofol was the chief cause of death in this case. Thanks to "B" for the tip!
Propofol has a very "steep" dose response curve. This means that the amount of drug required to induce sleep and the amount of drug required to cause death can be quite close to the same amount. e.g. one amount will cause the desired effect; a slightly higher dose death.
Because of this steep curve, the drug includes label warnings urging medical professionals who use the drug to have resuscitation equipment on hand at all times.
* According to a warrant issued to serve Dr. Murry's Offices "The Los Angeles Chief Medical Examiner-Coroner, Dr. (Lakshmanan) Sathyavagiswaran, indicated that he had reviewed the preliminary toxicology results and his preliminary assessment of Jackson's cause of death was due to lethal levels of propofol (diprivan)."
Why isn't this Drug a "controlled" subtance?
Since the drug is primarily used by the medical community in a surgical setting and the drug is not an opiate, the FDA has not yet placed this drug on the schedule of controlled substances. This will almost certainly change in time.
Why haven't I heard of Propofol before?
This drug is almost completely limited to surgical wards and hospital settings. it is not available by prescription nor is it an over the counter drug. As such people within the medical community will have heard of it (at least), but few others are likely to know what it is.
Why so Much Suspicion Re: Michael Jackson's Death
It is known to the medical establishment that it takes very large quantities of Propofol to induce and maintain sleep for hours on end. So much so, in fact, that there's little doubt that for Mr. Jackson to get up to six hours of sleep numerous vials of Propofol would have been required.
Abusers of the drug have stated that a single injection lasts no more than ten minutes.
The 200mg container pictured above is what is typically used to induce 1/2 hour of sedation. Repeated administration would therefore be required to induce multiple hours of sleep. This, in turn, suggests that the person administering this drug should have noticed something amiss far sooner than the (now) stated four hours between the star's death and the death being reported.
Dr. Conrad Murray Found Guilty of Manslaughter
November 8, 2011
After ten hours of deliberation the twelve person jury in the Michael Jackson "wrongful death" trial of Dr. Conrad Murray found the doctor guilty of involuntary manslaughter. This was a unanimous verdict.
Shortly after the verdict was read, the doctor's bail was revoked. He will be held in custody until the sentencing phase. Having been found guilty the doctor faces possible revocation of his medical license and up to four years of imprisonment.
Dr. Murray was given four years of incarceration, this is the maximum sentence allowed for a "wrongful death" conviction.