Whitney Houston died of accidental drowning -- but cocaine use and heart disease also contributed to her Feb. 11 demise at the age of 48, the Los Angeles County Coroner's Office told TheWrap on Thursday.
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The coroner's office did not say how much cocaine was in her system at the time of her death.
The singer also had marijuana, Xanax, benadryl and the muscle relaxant flexeril in her system, the coroner's office said, but those substances did not play a role in Houston's death.
The coroner's office maintained early on that there was no foul play in Houston's death.
Houston was found submerged in her bathtub at the Beverly Hilton hotel in Beverly Hills, Calif., the day before the Grammys, by a member of her personal staff.
Houston had suffered from substance addiction throughout her life. Emergency responders came to the scene, but were unable to revive her.
The singer was at the Beverly Hilton to attend the annual pre-Grammys party held by her producer and mentor Clive Davis.
Born in Newark, N.J., in 1963, Houston found fame early, scoring a No. 1 hit with the track "Saving All My Love for You" in 1985. More chart-toppers followed, including what would become her signature tune, Dolly Parton's "I Will Always Love You," which was included on the soundtrack of her 1992 film "The Bodyguard." All told, Houston has sold more than 170 million albums, singles and videos worldwide.
But along with the great success came personal troubles, often involving drug use. In 2000, personnel at a Hawaii airport found marijuana in the luggage of both Houston and her then-husband Bobby Brown. (The pair boarded their plane before authorities arrived,, and charges were dropped.)
Houston first admitted to drug use during an interview with Oprah Winfrey in 2009, telling Winfrey that she and Brown "would have ounces" of cocaine readily available, and that her preferred drugs of choice were marijuana laced with cocaine.
"You put [cocaine] in your marijuana, you lace it, you smoke it," Houston said.
Houston's ongoing battle with substance abuse would place her in rehab on more than one occasion, most recently in May 2011.
The singer is survived by her 19-year-old daughter, Bobbi Kristina Brown.