Initial tests have revealed that Matthew Perry did not have fentanyl or meth in his blood system when he died, according to reports.
While no drug paraphernalia is said to have been found at the scene, Perry, who shot to fame in the 1990s as wise-cracking Chandler Bing on the hit US sitcom, spoke openly of his alcohol and substance abuse issues in the past.
Los Angeles County medical examiner’s office confirmed on Tuesday that an autopsy on Perry was complete, but his exact cause of death has been “deferred” as it awaits a more in-depth toxicology report, which can take weeks.
US news outlet TMZ has now reported that early enquiries have confirmed fentanyl or meth overdoses have been ruled out, but whether other prescription medication played a part in Perry's death have yet to be determined.
At the time of his passing, Perry was said to be "sober and active in AA program".
Friends creator Marta Kauffman also stated that he seemed in good spirits during a recent phone call.
Writer and producer Kauffman, 67, remained firm friends with Perry after casting him in Friends almost three decades ago and last caught up with him two weeks ago.
Speaking to the National Broadcasting Company's (NBC) Today programme, she said that their last chat a fortnight ago had been "great".
"He didn't seem weighed down by anything," she said. "He was in a really good place, which is why this seems so unfair."
Perry's Friends co-stars Courteney Cox, Jennifer Aniston, Lisa Kudrow, Matt Le Blanc and David Schwimmer have paid tribute to him in a joint statement, saying that they are "utterly devastated" by his death.
"We were more than just cast mates. We are a family," they added.
"In time we will say more, as and when we are able," the statement continued. "For now, our thoughts and our love are with Matty’s family, his friends, and everyone who loved him around the world."