Actor Matthew Perry's death was ruled an accident caused by the acute effects of ketamine.

The actor, aged 54, was discovered unresponsive in a hot tub at his Los Angeles residence in October.

Perry's cause of death, according to a post-mortem examination, was determined to be the "acute effects of ketamine". Other contributing factors included drowning, coronary artery disease, and the effects of buprenorphine, a medication for opioid use disorder.

The County of Los Angeles Department of Medical Examiner confirmed on Friday that the cause of death was accidental.

Raffi Djabourian, the senior deputy medical examiner, said in his summary: “At the high levels of ketamine found in his post-mortem blood specimens, the main lethal effects would be from both cardiovascular overstimulation and respiratory depression.