The singer, 48, was also found to have cocaine in her system. Contributing factors of her death included heart disease and cocaine use, an investigation found. The report also found that Houston had marijuana, Xanax, Benadryl and other medication in her system.
"There was water found in her lungs that indicated to us that she was alive when she was submerged underwater," coroner chief Craig Harvey tells PEOPLE. "According to our tests, the level of cocaine was not necessarily a lethal level of cocaine. But her death was complicated by chronic cocaine use and heart disease."
"She could've passed out first due to the intoxication from the cocaine, or she could've had a heart attack and then drowned," Winter tells PEOPLE. "It's probably one of those two scenarios."
Coroner officials previously confirmed that prescription pill bottles were found in her room, but the number of pills were "not in alarming amounts."