Matthew Perry's friends express serious concern over his autopsy

Following the revelation of Matthew Perry's cause of death, his friends are showing deep concerns over his probable relapse.

A source revealed to US Weekly that his circle fears that the late actor may have died of drug overdose.

“He’s been struggling with sobriety for years. Every time he fell off the wagon there was a huge sense of shame," they stated.

The insider continued: "After Friends ended there was a lot of depression and disappointment in his career. He struggled with his mental health but never got help for it."

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Moreover, they revealed that Matthew dealt with his problem by isolating himself, "Since the show, he was financially taken care of and didn’t have to work, so it created an environment to use.”

The quotes come after the LA County Medical Examiner’s Office confirmed that the late actor died of acute effects of ketamine.

Matthew was reportedly on “ketamine infusion therapy” and got his last treatment around 10 days before his death, according to the autopsy report.

Opening up in an interview with PEOPLE magazine, he recalled the time he almost died because of the same treatment.

“I didn't know how to stop. If the police came over to my house and said, 'If you drink tonight, we're going to take you to jail,' I'd start packing. I couldn't stop because the disease and the addiction is progressive,” Matthew said.