The findings were based on toxicology screenings done on samples taken when the "Star Wars" actress arrived at a Los Angeles hospital.
Carrie Fisher had drugs in her system when she died, namely cocaine, ecstasy, methadone, and heroin, a new toxicology report revealed on Monday.
Fisher's toxicology review found evidence of cocaine, MDMA (better known as ecstasy), alcohol and opiates when she was rushed to Ronald Reagan UCLA Hospital on December 23, a toxicology report showed.
The Los Angeles acting chief coroner Dr Christopher Rogers recorded her cause of death as sleep apnoea, where breathing cuts out during slumber, and various other "undetermined factors".
According to the report, Fisher may have ingested the cocaine as early as three days before the flight, adding to the uncertainty about the cause of death. "We can not establish the significance of the multiple substances that were detected in Ms. Fisher's blood and tissue with regard to the cause of death".
In that document, in addition to sleep apnea as a possible cause of death are also heart disease and drug use, but States that the exact cause of death is unknown.
Fisher had a heart attack on a flight from London to Los Angeles on December 23rd previous year and was immediately rushed to the hospital.More news: Supreme Court strikes down law blocking disparaging trademarks
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Fisher died at age 60 on December 27, four days after she went into cardiac arrest on a flight from London to Los Angeles.
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"Ms. Fisher suffered what appeared to be a cardiac arrest on the airplane, accompanied by vomiting and with a history of sleep apnea", the final report stated. "She was purposefully open in all of her work about the social stigmas surrounding these diseases", Lourd told People.
She wrote: "Her personal assistant reported that the decedent (Fisher) was last awake and normal at the beginning of the flight".
Carrie Fisher is most well-known for her role as Princess Leia Organa in Star Wars films.
The Star Wars icon had a known history of drug addiction, which she had struggled with for decades. He noted that his sister wrote extensively about her drug use, and that numerous drugs she took were prescribed by doctors to try to treat her mental health conditions. Speaking previously, the blonde-haired beauty said: "My mom battled drug addiction and mental illness her entire life".
Reynolds, who was 84, suffered a fatal stroke the day after her daughter's death.