The 'Friends' star tragically passed away in October

According to the County of Los Angeles Department of Medical Examiner, contributing factors to the actor's death included coronary artery disease, drowning, and buprenorphine (an opioid used to treat opioid use disorder, acute pain, and chronic pain).

Perry was found unresponsive at his LA home in his swimming pool and was pronounced dead at the age of 54 by paramedics at the scene.

An autopsy report revealed that the actor was 'receiving ketamine infusion therapy for depression and anxiety' with the most recent dose reportedly taken a week and a half before his passing.

"The ketamine in his system at death could not be from that infusion therapy, since ketamine’s half-life is three-to-four hours or less," the report stated.

Perry also had 'reportedly clean for 19 months', according to the report.

Associated Press reports that after a review of the autopsy at their request, Dr Andrew Stolbach, a medical toxicologist with Johns Hopkins Medicine, determined that the amount of ketamine detected 'would be enough to make him lose consciousness and lose his posture and his ability to keep himself above the water'.

“Using sedative drugs in a pool or hot tub, especially when you’re alone, is extremely risky and, sadly, here it’s fatal,” Dr Stolbach also told the outlet.

During his final years, the 'Friends' star had been very open about his drug addictions, using his experience to help others in similar situations.

In his memoir, 'Friends, Lovers and the Big Terrible Thing', he opened up about his battle with addiction and admitted that he almost died once before, when he was 49 years old.

The actor confessed that he spent two weeks in a coma and five months in the hospital and had to use a colostomy bag for nine months after his colon burst from opioid overuse.

"The doctors told my family that I had a 2 percent chance to live," he wrote.

"I was put on a thing called an ECMO machine, which does all the breathing for your heart and your lungs. And that’s called a Hail Mary. No one survives that.”

The Matthew Perry Foundation was founded on November 3rd to continue Perry’s work of helping others who face struggles with addiction.

Last month, his friend and former co-star, Jennifer Aniston, asked her followers on her Instagram account to show support for the foundation.

“For #GivingTuesday please join me and Matty’s family in supporting his foundation—which is working to help those suffering with addiction," Aniston wrote.

“He would have been grateful for the love.”

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