Whitney Houston Official Cause of Death Released; Cocaine Found in System

When Whitney Houston was found dead in her hotel room bathtub at the Beverly Hilton in Los Angeles on Feb. 11, much of the discussion focused on the singer's history of substance abuse.

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The Los Angeles County Coroner's office issued her official death Thursday, ruling it an accidental drowning. A coroner rep tells The Hollywood Reporter that the drowning is being attributed to atherosclerotic heart disease and cocaine use.

No evidence of cocaine was found on the scene, but the drug was found in her system.

Houston, whose drug use and erratic behavior had eclipsed her storied music career, died the day before the Grammy Awards at age 48. The "I Will Always Love You" superstar's body was found submerged underwater in a bathtub on the fourth floor of the hotel, and when emergency medics arrived, it was too late. She could not be revived and was pronounced dead half an hour after 911 was called.

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Police ruled out foul play, and autopsy results were delayed pending an investigation into the cause of death. Meanwhile, speculation brewed, with outlets like TMZ suggesting it was a lethal combination of prescription medication and alcohol. The site reported that multiple bottles of medication were found at the scene containing a small amount of pills including the anti-depressant Xanax, ibuprofen and amoxicillin for a sore throat.

Police investigators served subpoenas to doctors and pharmacies in order to determine whether prescription drugs felled the star.

Houston was buried Feb. 19 in a New Jersey cemetery following a star-studded memorial at her childhood church in Newark.

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In her will, she left everything to daughter Bobbi Kristina Brown, her only child with ex-husband Bobby Brown. The 19-year-old will receive her mother's money, furniture, clothing, personal effects, jewelry and cars -- all of which has been placed in a trust until she turns 21.

In a sit-down with Oprah Winfrey that aired March 11, Bobbi Kristina called Houston an "angel."

"Everything people are saying about her -- all that negativity -- it's garbage. That's not my mother," she said.