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OTRC: Whitney Houston death: Medical records ordered for investigation

Subpoenas for Whitney Houston's medical and pharmacy records have been issued by the Los Angeles County Coroner's Office, in a routine move that could speed up its investigation into the iconic singer's mysterious death.

The 48-year-old died at the Beverly Hilton hotel in Beverly Hills, California on Saturday, February 11. Members of her staff found her unconscious and underwater in a bathtub and paramedics were unable to revive her.

Her autopsy has been completed but the results will not be released until a toxicology report is produced, which could take up to eight weeks. Assistant Chief Coroner Ed Winter told the Associated Press that his office had contacted "a number of doctors" to try and obtain Houston's records.

He had previously confirmed that bottles of prescription drugs were found near her body on the day she died. A source close to the matter told OnTheRedCarpet.com that one of them was the antibiotic amoxicillin.

Mixed with alcohol, some medications can cause death. It is unclear what substances Houston ingested on the night she died. The singer had struggled with addictions to drugs such as cocaine and pills and alcohol for years. She relapsed and returned to rehab in May. Witnesses say they saw Houston drinking champagne the night before her death.

Two days before she died, she celebrated and performed at a Los Angeles nightclub in what marked her final performance, although it is unclear whether she consumed alcohol (check out photos and video from the event).

Beverly Hills Police Department Lt. Mark Rosen told OnTheRedCarpet.com and other reporters on Monday that police have carried out a preliminary death investigation and are not treating the matter as a criminal case, but have "not ruled anything out."

On the day of her death, investigators for the Los Angeles County Coroner's Office worked inside the hotel room where she died as celebrities poured into the building for a pre-Grammy gala that Houston was supposed to attend. Producer Clive Davis, her mentor, dedicated the event to her (see photos). The party featured performances from the likes of Alicia Keys and also handed out the President's Merit Award to Virgin Group founder Sir Richard Branson.

Houston, who had six Grammy Awards, was known for songs such as her cover of Dolly Parton's ballad "I Will Always Love You" and "I'm Every Woman," originally sung by Chaka Khan. Both tracks were featured on the soundtrack of the 1992 movie "The Bodyguard," which marked Houston's film debut.

Khan recently slammed Davis' decision to go ahead with his pre-Grammy gala, calling it "complete insanity."

"Knowing Whitney, I don't believe she would've said the show must go on," she said on "Piers Morgan Tonight" in an interview that aired on February 13. She was the kind of woman that would've said, 'Stop everything! Uh uh. I'm not going to be there.'"

Houston's body was flown to her native state of New Jersey on Tuesday. Her funeral is planned for Saturday at noon and will take place at the New Hope Baptist Church in Newark, where she grew up and showcased her singing talents as a child.

The event will likely be by invitation only and no wake or public memorial is planned, according to WABC Television, the sister station of OnTheRedCarpet.com's parent company, KABC Television.

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