Whitney Houston's preliminary autopsy results are in, and RadarOnline.com has exclusively learned that sedatives, specifically benzodiazepines, were in the late pop singer's system. Xanax, lorazepam, and valium are all benzodiazepines.

Los Angeles County Coroner Assistant Chief Ed Winter told the media on Tuesday that toxicology results could take from 4-6 weeks, but that preliminary results might be made public this week.