The "Friends" star died from acute effects of ketamine and other contributing factors, the autopsy shows.
LOS ANGELES -- Matthew Perry died from the acute effects of ketamine, according to the autopsy report released Friday by the Los Angeles County coroner.
The autopsy listed drowning, coronary artery disease and buprenorphine effects as contributing factors not related to the immediate cause of death. The manner of death was ruled an accident.
The "Friends" actor was found dead at his Pacific Palisades home on Oct. 28, per police and law enforcement sources who spoke to ABC News. He was 54.
In a statement the day after responding to his home, the Los Angeles Police Department said Perry "was discovered by a witness unresponsive in his jacuzzi."
According to the autopsy report, Perry was on ketamine infusion therapy, with the most recent therapy 1 1/2 weeks before death.
He had high levels of ketamine in his blood, and likely lapsed into unconsciousness and then went under the water, the autopsy report said.
He was reported to have been receiving ketamine infusions for depression and anxiety, according to the report, but the medical examiner writes the ketamine in his system at death could not have been from that infusion therapy because ketamine's half life is 3 to 4 hours or less. His method of intake is listed as unknown.
Prescription drugs and loose pills were found at his home, but nothing close to the pool where he was found dead, the report said.
Perry played Chandler Bing on "Friends" from 1994 to 2004, a life-changing role that made him a household name and earned him an Emmy nomination. Playing Chandler, Perry's quick wit, sarcasm and charm were on full display -- ultimately helping him hide an addiction to alcohol and prescription painkillers triggered after a doctor prescribed him Vicodin following a jet ski accident.
At one point, he told Diane Sawyer in an interview for "20/20" in 2022, he was taking 55 pills a day.
Perry recalled how the "Friends" cast -- including Jennifer Aniston, Courteney Cox, Lisa Kudrow, David Schwimmer and Matt LeBlanc -- rallied around him.
"In nature, when a penguin is injured, the other penguins group around it and prop it up until it's better. This is what my costars on 'Friends' did for me," he wrote in his 2022 memoir, "Friends, Lovers, and the Big Terrible Thing."
Perry would continue to struggle for decades, ultimately overcoming his demons and dedicating his life to helping others who might be struggling.
"Addiction, the big terrible thing, is far too powerful for anyone to defeat alone, but together, one day at a time, we can beat it down," he wrote in his book.
Perry told Sawyer: "For some reason, it's obviously because I was on 'Friends,' more people will listen to me. So, I've gotta take advantage of that, I've gotta help as many people as I can."
In addition to speaking out about his struggles and recovery, Perry also established a sober house to aid others in their struggle with addiction.
"What's interesting about it is I've stood on a stage helping 100,000 people at the same time, but I get the same juice, I get the same thing, from helping one person," he told "Good Morning America" in 2022.
"And how far down the scale I've gone, which is all a part of this book, that's how low I can then help people," he continued. "If they've gone through anything close to what I went through, I can come in and help."
In an interview on the "Q With Tom Power" podcast in 2022, Perry opened up about how he wanted to be remembered.
"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," he said.
"When I die, I don't want 'Friends' to be the first thing that's mentioned," Perry continued. "I want [helping people] to be the first thing that's mentioned, and I'm gonna live the rest of my life proving that."
ABC News contributed to this report.