Ketamine is a powerful active ingredient used by health authorities to induce and maintain anesthesia in patients, and the US Department of Justice has listed ketamine as an illegal drug. 

The cause of death of Matthew Perry, known for his character 'Chandler' in Friends, has been determined.

"The Los Angeles County Department of Medical Examiners (DME) has determined that the cause of death of 54-year-old actor Matthew Langford Perry was the acute effects of ketamine. Factors contributing to Perry's death include drowning, coronary artery disease and the effects of buprenorphine (used to treat opioid use disorder). The manner of death was accidental."

Revolutionary decision: National Bullfighting Award abolished! Revolutionary decision: National Bullfighting Award abolished!

Perry wrote a book about drug and alcohol addictions called 'Friends, Lovers and the Big Scary Thing' and said of addiction, "Addiction is the scariest thing, too powerful for anyone to beat alone. But together, we can beat it one day."

FAREWELL MESSAGES FROM FRIENDS TO MATTHEW PERRY

Courtney Cox, one of the famous actors who starred in the Friends series, said, "I am so grateful for every moment I had with you, Matty, and I miss you every day," while Lisa Kudrow said, "Thank you for the best 10 years a person has ever had. Thank you for trusting me. Thank you for everything I have learned about grace and love from knowing you. Thank you for the time I spent with you, Matthew."

David Schwimmer's condolence message said, "Matty, thank you for ten incredible years of laughter and creativity. And you had the heart to be generous and share it with us so we could build a family of six strangers. This photo is from one of my favorite moments with you. Now it makes me smile and mourn at the same time."

Jennifer Aniston said, "Matty, I love you so much and I know you are now completely at peace and not in pain. Rest up little brother. You always made my day," while Matt LeBlanc said of Pery, "It is with sadness that I say goodbye. The times we spent together are honestly some of my favorite times of my life. I will always laugh when I think of you and I will never forget you. Never."