Who says cocaine is ok as a recreational drug. Check out the autopsy results. Drugs wasted another superstar! LOS ANGELES (Reuters) - Pop star Whitney Houston died of accidental drowning due to the effects of cocaine use and heart disease, a Los Angeles County coroner's spokesman said on Thursday. The 48-year-old singer, who spent years battling addiction to drugs including cocaine, was found submerged in the bathtub of her Beverly Hills hotel room on February 12, the eve of the Grammy Awards. An autopsy into Houston's death found that the cause of death was accidental drowning with atherosclerotic heart disease and cocaine use listed as contributing factors, Los Angeles County Coroner's spokesman Craig Harvey said. Harvey said toxicology tests also turned up marijuana, an anti-anxiety medication, a muscle relaxant and an anti-histamine in Houston's system. Those drugs were not found to have contributed to her death, and no trauma or foul play were suspected, the coroner's office said. A final report was expected to be made public within two weeks.