The actor - who shot to fame playing Chandler on NBC sitcom 'Friends' from 1994 to 2004 and was killed on 28 October, 2023, aged 54 from the "acute effects" of anaesthetic ketamine after receiving three injections of the drug - has had the circumstances of his death questioned by his ex-employee Kayti Edwards.
She said in a chat with the Daily Mirror newspaper: "If you have given him a big shot, there would be a needle and evidence of ketamine in the house.
"Where did it all go? Why did the assistant shoot him up with all those drugs and leave.
"I always stayed with Matthew if he was taking drugs as I didn't want him to OD, or anything to happen. I could call 911.
"But why wasn't his assistant there?"
Kayti, 47, was Matthew's assistant in 2011, and she dated the 'Friends' star in 2006, with the pair staying friends until his death.
Matthew's assistant Kenneth Iwamasa, 59, has told authorities he administered three doses of ketamine by injection to the actor on the day he died.
But Kayti said: "When I heard that he let his assistant do it, I just couldn't understand, especially as he had no medical training."
Iwamasa was among five people indicted over Matthew's death, and he has already pleaded guilty to conspiring to distribute ketamine causing death.
He admitted in plea deal papers to "repeatedly injecting Perry with ketamine without medical training".
US Attorney Martin Estrada said two doctors charged in connection to the actor's death "cared more about profiting off of Mr Perry than caring for his well-being".
He added: "Matthew Perry's journey began with unscrupulous doctors who abused their position of trust because they saw him as a payday, to street dealers who gave him ketamine in unmarked vials."