Haim dizzy, stumbling with flu before death

Corey Haim had been suffering from flu-like symptoms for several days before finally stumbling in front of his mother at her Los Angeles apartment early Wednesday morning, a coroner spokesman confirms.

"Some time after midnight, he got up, he was dizzy and unsteady on his feet and knelt down," L.A. County Coroner Assistant Chief Ed Winter tells PEOPLE. "His mom helped him to a bed and he became unresponsive in about a minute or so. She dialed 911 and he was pronounced dead at a local hospital at 2:15 a.m."

The death of the former '80s heartthrob at age 38 has been ruled inconclusive pending an autopsy and toxicology test. But Winter says, "LAPD believes it was a possible drug overdose."

Haim had been living with his mother as she battled cancer, Judy Haim tells RadarOnline. "I am a cancer victim and Corey was helping me at home,” she said. "He was a good boy. I’m devastated by his death."

Winter confirms that four prescription medication bottles were found in the home in Corey Haim's name. Winter wouldn't verify what drugs they were, though he says no illegal drugs were found.

Haim's mother told investigators that her son "had problems with prescription meds and that he had been in rehab on and off over the years," Winter says.