Friends star Matthew Perry, who died on October 28 due to the effects of ketamine, had undergone ketamine therapy for depression.

Perry, the much-loved comedic actor, forever immortalized as Chandler Bing on the hit 1990s sitcom Friends, was found dead on October 28 at his Los Angeles home at the age of 54.

Several weeks after his death, the County of Los Angeles Department of Medical Examiner released an autopsy listing Perry’s death as acute effects of ketamine. Drowning, coronary artery disease, and buprenorphine, which is used to treat opioid use disorder, were also listed as contributing factors.

Perry, who was public about his struggles with substance abuse, had been undergoing ketamine infusion therapy more than a week before his death as part of his mental health treatment, according to a report by Yahoo! Life.

While ketamine — which can cause hallucinogenic effects, feelings of dissociation, and euphoria — became a popular club drug in the 1990s, known as “Special K,” it was also approved in 1970 by the Food and Drug Administration (FDA) to use as an anesthetic, the report noted.

Ketamine is believed to have the ability to target glutamate receptors in the brain, which can make the brain form new neural connections, and has long been studied for its potential mental health benefits, specifically in managing treatment-resistant depression and suicidal ideation.

Taking too high of a ketamine dose, or taking it too frequently, however, can also result in cardiac issues, seizures, and cognitive issues.

​​Dr. Steven Levine, a board-certified psychiatrist who developed the protocol for the clinical use of ketamine in 2011, previously told Yahoo that ketamine can “enable the brain to heal and change and learn and become more resilient,” due to its effect on glutamate receptors.

“This is important for people with depression or who have suicidal thoughts, as they are stuck in patterns of negative thinking and need help breaking through,” Yahoo reported.

Levine also told the outlet that “Only about 50% will respond to ketamine treatments, maybe 60 to 70% will have that sort of lower bar of clinically meaningful results.”

“So lots of people aren’t going to get this great benefit from ketamine,” Levine added. “But I have seen people who really were at the end of their rope, who tried everything under the sun — people who really believe that there was nothing on earth that could help them. I’ve seen some really amazing dramatic responses.”

Notably, Perry wrote about receiving ketamine treatments in his 2022 memoir, Friends, Lovers, and the Big Terrible Thing, which focused on his struggles with substance abuse.

“There is a synthetic form of [ketamine] now, and it’s used for two reasons: to ease pain and help with depression. Has my name written all over it — they might as well have called it ‘Matty,'” he wrote. “Ketamine felt like a giant exhale. They’d bring me into a room, sit me down, put headphones on me so I could listen to music, blindfold me, and put an IV in.”

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