Assistant Chief Coroner Ed Winter declined to identify the drugs. Haim was battling flulike symptoms in the days before he died.
Winter said an autopsy was done Thursday, but his office was awaiting the results of toxicology tests that could take two months before determining a cause of death.
Haim died Wednesday at age 38 after collapsing at his mother's apartment. The actor battled drug addiction for years.
He earned fame for roles in the 1980s films "Lucas" and "The Lost Boys." He recently completed several film projects.
"Access Hollywood" reported on its Web site that Judy Haim had been told by the coroner's office that her son had an enlarged heart and his lungs were filled with water.
Winter confirmed his office had called Judy Haim, but he declined to say what they discussed.
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