“Friends” actor Matthew Perry died as a result of “the acute effects of ketamine,” the Los Angeles County Medical Examiner’s office said Friday.

Perry, who played Chandler Bing on the hit TV sitcom from 1994-2004, died at the age of 54, having struggled for decades with addiction and related serious health issues.

“Contributing factors in Mr. Perry’s death include drowning, coronary artery disease and the effects of buprenorphine (used to treat opioid use disorder),” the medical examiner said in a statement. “The manner of death is accident. ”

Perry was found unconscious in a hot tub at his house in Los Angeles on October 28. First responders were unable to revive him, and an initial post-mortem proved inconclusive, pending a toxicology report.

Doctors and veterinarians often employ ketamine as an anesthetic, and researchers explore it as a treatment for depression. Underground users take it illicitly for its hallucinogenic effects.

“Friends,” which followed the lives of six New Yorkers navigating adulthood, dating and careers, drew a massive global following.