Whitney Houston May Have Drowned in Tub, Taken Xanax Before Death

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Reports have begun to roll in about Whitney Houston's final hours and what may have caused her untimely death.

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TMZ reports that Houston was found submerged in her bathtub at the Beverly Hilton hotel by her stylist, hairdresser and two bodyguards. Houston's entourage became worried about the singer because she had been in the bathroom for over an hour, and it was time to prepare for the Clive Davis pre-Grammy party, where she had planned to perform.

The hairdresser went in to check on Houston, and found the singer in the tub with her face under water and her legs up, looking as though she slid down the back of the tub. Bodyguards attempted CPR on Houston, who remained unresponsive. Paramedics arrived shortly thereafter, and the singer was pronounced dead at 3:55 PM.

TMZ also reports that the singer had a prescription for the drug Xananx, which she took to calm her nerves before big performances, like the pre-Grammy party she was scheduled to perform at Saturday evening, though sources close to Houston say she did not mention taking the drug on Saturday. Various prescription medication bottles are reported to have been found in her room when paramedics arrived.

An unnamed law enforcement official told RadarOnline.com that the singer had a "plethora of sedatives including Lorazepam, Valium, Xanax, and a sleeping medication" in her hotel room.

The prescription drugs were taken into custody by the Beverly Hills Police Department. An autopsy is expected to take place either Sunday or Monday.

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Reports say that Houston had been in a good mood all day and was excited to perform that evening. Hours before her passing, she had phone conversations with her mother, gospel singer Cissy Houston, as well as her cousin, famed singer Dionne Warwick. Both women say they talked to Houston about attending that evening's pre-grammy party and that nothing seemed out of the ordinary.