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Propofol may have killed Joan Rivers

Propofol killed Michael Jackson and may have played a role in death of comedian Joan Rivers
Image: David Shankbone/Flickr

Comedian Joan Rivers' death in September after vocal cord surgery might have been avoidable, according to a new federal health report, and the drug propofol seems to have played a role.

If propofol sounds familiar, that's because it was also implicated in Michael Jackson's death in 2009; sources indicate that he was using it off-label as a sleep aid at the time of his death.

So what is this drug that has been involved in the recent deaths of two of our most beloved stars?


First tested in the 1970s, propofol is one of the most popular anesthetics in use worldwide. It became more widespread because it caused fewer side effects (like nausea) and a faster recovery time in patients than similar drugs. It's even listed on the World Health Organization's list of essential medicines.

Surprisingly, scientists only recently learned how exactly general anesthetics like propofol (as opposed to local anesthetics like Novocain) work in the body, even though they have been used in one form or another for over 150 years.

Propofol enters the bloodstream and makes its way to the brain, where it attaches to cells at a particular spot called the GABAA receptor. This message is transmitted through the entire central nervous system, slowing cell activity in the whole body, and allowing surgeons to operate on patients without pain.

Structure of a propofol molecule. Image: Fuse809/Wikimedia Commons

Propofol is administered through an injection by an anesthesiologist. The dose that the anesthesiologist gives to patients depends on the patient's size and other medications and conditions.

Dosing is a delicate balance because of how quickly propofol affects the body: too little, and the patient won't be sufficiently sedated, too much, and her breathing or heart could stop. "The issue with propofol is that it can make the patient's brain forget to breathe. It's not a side effect or complication; it's just what it does," reads a blog by Benjamin Wedro, a doctor specializing in emergency care. Without proper monitoring, a patient could die on the operating table from too much anesthetic or from an allergic reaction to it.

"The issue with propofol is that it can make the patient's brain forget to breathe."

There are risks when a patient is put under, but the average person receiving general anesthetic is pretty unlikely to die from it. Deaths caused by propofol are often due to abuse (as is suspected with Michael Jackson's death) or improper monitoring. The federal health report indicates that the latter was likely one of the causes for Joan Rivers' death.

Doctors around the world already use a number of alternatives to propofol; intermittently over the past few years, their reliance on these other drugs has been even higher because of a Propofol shortage. Some competing anesthetics, like Lusedra, have not lived up to their promise suggested by initial clinical trials.

So for now propofol is still the most popular anesthetic in the country. The best way to prevent future deaths, doctors say, is to ensure that patients are closely monitored while they are under anesthesia. With better protocols and professionals standing by just in case, hopefully propofol can keep anesthetizing patients with less risk.