Los Angeles, California (CNN) -- Corey Haim seemed to be winning his battle against drug abuse in the weeks before his death, according to both his manager and closest friend.
The 1980s teen movie actor and heartthrob died Wednesday at 38 after collapsing in the Los Angeles apartment he shared with his mother, authorities said.
Haim was "weaned down to literally zero medications" in the last two weeks by an addiction specialist, manager Mark Heaslip said Wednesday on "Issues With Jane Velez-Mitchell" on HLN, CNN's sister network.
The doctor "put him on a new line of medications," Haim's longtime friend and frequent co-star Corey Feldman said Wednesday on CNN's "Larry King Live."
Feldman pleaded with people not to draw conclusions that Haim died from a drug overdose. He said that until the autopsy report is issued, "nobody knows and nobody's going to know."
"I know that there were symptoms that he was showing that expressed it could be a number of things," Feldman said. "This could have been a kidney failure. This could have been a heart failure."
Heaslip said Haim's mother, Judy, told him "there were no signs of him overdosing."
The actor's death came as his career was picking up, with Haim booking "movie after movie," Heaslip said. His latest film is set for release soon, he said.
Haim "really became a man" in recent months as he helped his mother in her battle with cancer, Feldman said. "He's been there for her, taking care of her, being responsible," he said.
Haim was taken to Providence St. Joseph Medical Center in Burbank, California, where he was pronounced dead at 2:15 a.m. PT (5:15 a.m. ET) Wednesday, Los Angeles County Deputy Coroner Ed Winter said.
Haim was in the apartment he shared with his mother when he "became a little dizzy, he kind of went to his knees in the bedroom," Winter said. "His mom assisted him in the bed. He became unresponsive."
His mother called paramedics to the apartment, which is between Hollywood Hills and Burbank, he said.
Los Angeles Police Sgt. Frank Albarran said earlier that Haim's death appeared to be accidental and may have been because of an overdose.
Haim had suffered flulike symptoms for two days, the deputy coroner said.
"We found no illicit drugs; however, we did recover four of his prescription meds at the location," Winter said, adding he does not know what those drugs were.
An autopsy, including toxicology tests, will be conducted, Winter said, but it is likely to be weeks before any conclusions are made public.
The actor was under the care of his doctor, who visited him Tuesday night, as well as another doctor who specializes in treating addictions, Heaslip said.
Feldman said he was angry about how the entertainment industry had snubbed Haim in recent years. His friend was broke, without a car and living in a month-to-month rental apartment with his mother, he said.
"We build people up as children, we put them on pedestals and then when we decide that they are not marketable anymore, we walk away from them," he said.
Haim's most famous role was in the 1987 movie "The Lost Boys" with Feldman. Haim played the role of a fresh-faced teenager whose brother becomes a vampire.
In later years, the two friends -- who appeared in eight movies together -- struggled with drug abuse and went their separate ways. They reunited for a reality show, "The Two Coreys," in 2007, but A&E Network canceled the program after slightly more than a year.
In a 2007 interview on "Larry King Live," Haim and Feldman discussed their battle with drugs. Feldman told King that he had gotten clean, but it took Haim longer.
Haim called himself "a chronic relapser for the rest of my life."
"I think I have an addiction to pretty much everything," he said. "I mean, I have to be very careful with myself as far as that goes, which is why I have a support group around me consistently."
In 2008, Feldman told People magazine that he would no longer speak to Haim until his former co-star got sober. In a clip from "The Two Coreys," Feldman and his wife, along with two other former teen stars, called on Haim in an effort to get him to admit he needed help, the magazine said.
The meeting followed an incident in which Haim, scheduled to film a cameo appearance in a direct-to-DVD sequel to "The Lost Boys," appeared on the set "clearly under the influence," People reported.
Feldman told King on Wednesday that he renewed his contact with Haim in the past year because of the progress he made against his addiction.
Haim was born December 23, 1971, in Toronto, Ontario, according to a biography on his Web site. He made his first television appearance in 1982 on the Canadian series "The Edison Twins." His first film role was in the 1984 American movie "First Born."
Haim also won rave reviews for his title role in the 1986 film "Lucas." Film critic Roger Ebert said of him at the time, "If he continues to act this well, he will never become a half-forgotten child star, but will continue to grow into an important actor."
Following "The Lost Boys," Haim and Feldman appeared in "License to Drive" and "Dream a Little Dream."