CNN  — 

“Friends” star Matthew Perry died as a result of “acute effects of ketamine” and subsequent drowning, an autopsy report shows.

The report, released Friday by the Los Angeles Medical Examiner’s Office, shows Perry’s blood tested positive for ketamine, which is known to treat depression and anxiety.

“At the high levels of ketamine found in his postmortem blood specimens, the main lethal effects would be from both cardiovascular overstimulation and respiratory depression,” the report states. The death was ruled an accident, according to the report.

Perry was found floating face down in the pool of his Pacific Palisades home on October 28. Authorities said at the time that no foul play was involved.

The actor, 54, was found “unconscious in a stand-alone jacuzzi,” a spokesperson for the LA Fire Department told CNN in a statement at the time.

Perry was “reported to be receiving ketamine infusion therapy for depression and anxiety,” the autopsy report states.

The report further explains that ketamine has medical and surgical uses as an anesthetic and is also known as a recreational drug “mainly due to its ‘dissociative’ nature, indicating disconnection of mind and body. It can also have short duration hallucinatory and psychedelic effects.”

Perry’s last known treatment was a week and a half prior to his death, the autopsy states, well beyond the time it would still be in his system from the treatment.

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Matthew Perry is best known for his role as Chandler Bing on "Friends."
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Perry, pictured circa 1985, developed an interest in acting after moving to Los Angeles when he was a teen. He was born in Williamstown, Massachusetts, to an actor father and a journalist mother.
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Perry and Christina Applegate were cast in the 1988 made for TV teen movie "Dance 'til Dawn."
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Actress Martha Plimpton and Perry are seen at the Limelight nightclub in New York City circa 1988.
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Perry guest stars in an episode of "Growing Pains" in 1989. His character was injured in the episode, which was about the dangers of drunk driving.
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Perry co-starred in "Friends" with Matt LeBlanc, Lisa Kudrow, David Schwimmer, Courteney Cox and Jennifer Aniston. The first season aired in 1994.
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Perry is seen in the 1995 "Friends" episode "The One with the Evil Orthodontist."
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The cast of "Friends" drink milkshakes in an iconic promo photo.
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Perry and Cox appear on "The Tonight Show with Jay Leno" in 1996.
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Perry co-stars with Salma Hayek in the 1997 romantic comedy film "Fools Rush In."
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The cast of "Friends" pose for a promo shot in 1999.
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The sixth season of "Friends" aired in 1999.
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Perry and Cox are seen in the 2000 "Friends" episode "The One With Rachel's Assistant."
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Michael Clarke Duncan tackles Perry in a scene from the 2000 film "The Whole Nine Yards."
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Perry and Cox pose for a photo during the 2001 "Friends" episode "The One With Monica And Chandler's Wedding."
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Perry portrayed Joe Quincy on "The West Wing" in 2003, seen here alongside Amy Stewart, Richard Schiff and Milo O'Shea.
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Perry and British actress Kelly Reilly perform a scene from the West End play "Sexual Perversity in Chicago" at The Comedy Theatre in London in 2003.
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Perry competes in the Merv Griffin Beverly Hills Country Club Celebrity Tennis Classic in 2003. Growing up, Perry pursued his passion for tennis and became a top-ranked tennis player in Canada, where he lived with his mother after his parents split.
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Perry prepares to make a statement as fellow "Friends" cast member LeBlanc hands over the award they won for favorite television comedy series at the 2004 People's Choice Awards.
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Perry made his directorial debut in a 2004 episode of "Scrubs." He is seen here talking to director of photography John Inwood as actors Zach Braff, left, and John C. McGinley look on.
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Perry co-stars with Amanda Peet and Bruce Willis in the 2004 sequel "The Whole Ten Yards."
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Perry participates in a Screen Actors Guild rally in solidarity with the striking Writers Guild of America in Los Angeles in 2007.
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Perry speaks onstage at the Primetime Emmy Awards in 2012. He was nominated four times for the prestigious TV acting award.
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Perry throws out the ceremonial first pitch at a Los Angeles Dodgers game in 2012.
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Perry testifies before a House Subcommittee on the need to fund drug courts at the Capitol in 2013. Perry, who was open about his struggles with addiction, was an ambassador for the National Association of Drug Court Professionals.
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Perry and Lindsay Sloane are seen behind the scenes on a 2014 episode of the CBS series "The Odd Couple."
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Perry plays Ted Kennedy in the 2017 TV series "The Kennedys After Camelot."
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The cast of "Friends" appeared on "The Late Late Show with James Corden" in 2021.
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Copies of Perry's memoir, "Friends, Lovers, and the Big Terrible Thing," are displayed at a bookstore in 2022.
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Perry enters the stage for a conversation with editor Matt Brennan during the Los Angeles Times Festival of Books in Los Angeles in 2023.

A live-in assistant found Perry’s unresponsive body in the pool after returning home from running errands, the investigative summary of his autopsy report shows.

“The assistant jumped into the pool, moved the decedent into a sitting position on the steps, and called 911,” says the report.

Drowning is considered a contributing factor to Perry’s death “due to the likelihood of submersion into the pool as he lapsed into unconsciousness,” the autopsy states.

“The assistant did not report any recent illnesses, complaints, drinking, or drug abuse,” the report states.

What medical experts are saying

Ketamine is a powerful medication used in hospitals primarily as an anesthetic, although studies have also found that it has significant promise in treating severe depression, anxiety and suicidal ideation. It can be used illegally as a club drug that creates an intense high and dissociative effects.

In 2019, the US Food and Drug Administration approved a close relative called esketamine, which is used as a nasal spray, for treatment-resistant depression.

Experts say that although the levels of ketamine in Perry’s system were very high, it’s unclear whether they would have been deadly on their own.

Dr. Ed Boyer, a professor of emergency medicine at the Ohio State University Wexner Medical Center, said that “the elevated concentrations of ketamine suggest high levels of use.”

“Considering his last ketamine therapy was at least a week before, misuse – even recreational use – cannot be ruled out,” he added

Dr. Victor Weedn, a professor in the George Washington University Department of Forensic Sciences, said that people can react differently to different levels of ketamine and that it could become fatal because of its effects on breathing.

01:38 - Source: CNN
'Friends' star, Matthew Perry, dead at 54

Perry was ‘happy’ and ‘heathy’ before his death

Perry was open about his past experience with addiction. While promoting his book “Friends, Lovers, and the Big Terrible Thing: A Memoir,” which was released in November 2022 and addressed his addiction at length, Perry said on the “Q With Tom Power” podcast, “The best thing about me, bar none, is that if somebody comes to me and says, ‘I can’t stop drinking, can you help me?’ I can say ‘yes’ and follow up and do it.”

The autopsy report this week notes that Perry had reportedly not used drugs for 19 months before his death. It also states that though he was a “heavy tobacco user for many years,” he was not a smoker when he died.

His “Friends” costar Jennifer Aniston said this month that she had been in contact with Perry on the day of his death, and that he “was happy.”

“I was literally texting with him that morning, funny Matty,” she said in an interview with Variety. “He was not in pain. He wasn’t struggling.”

“He was happy. He was healthy,” she added. “He had quit smoking. He was getting in shape.”

Katherine Dillinger and Nadia Kounang contributed to this report.

This story has been updated with additional information.