Friends star Matthew Perry's death has been ruled as an accident from the "acute effects of ketamine".
The County of Los Angeles Department of Medical Examiner ruled the 54-year-old's death included drowning, coronary artery disease and the effects of buprenorphine.
Perry was found unresponsive in the swimming pool at his home on October 28.
He was pronounced dead by paramedics at the scene and a post-mortem was carried out the following day.
Matthew PerryGETTYPerry released his tell-all memoir just months before his death which included shocking details about his battles with drug and alcohol addiction.
The American-Canadian actor claimed he had been 18 months sober in October 2022.
Perry's friends maintain he was clean and sober at the time of his death.
Investigators did not find any illegal drugs when they arrived at the scene.
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Actor Matthew Perry (L) and studio executive Peter Roth attend Game One of the NBA FinalsReuters
Matthew Perry's haunting last Instagram post shows him relaxing in jacuzzi where he drownedHowever, prescription medication which was properly labelled and kept in storage bottles was found.
Perry was prescribed opiates in 2018 after his colon exploded, his memoir Friends, Lovers and the Big Terrible Thing revealed.
This prompted him to turn to street dealers to supply him with potentially fatal fentanyl-laced OxyContin.
He wrote: "The street pills were something like $75 per pill, so I was giving the guy $3,000 at a time, many times a week."
Perry appeared on the BBC in 2013 to debate addiction with Mail on Sunday columnist Peter Hitchens.
Matthew PerryREUTERSIn the heated debate, Perry said: "I am a drug addict.
"I am a person that, if I have a drink, I can't stop."
He added: "I am in control of the first drink so I do all the things to protect myself from having the first drink.
"But once I have that drink, the allegy of the body kicks in.
"This is all documented alcoholism proof. Then I can't stop that."