Actor Heath Ledger's drug intake before his death indicated it was likely he was an addict, America's best known addiction expert says.

Dr Drew Pinsky also says disgraced AFL star Ben Cousins should not play football at any level until he completes substance abuse treatment.

The Los Angeles-based Pinsky said Ledger's drug consumption was not a secret in Hollywood.

"There were people who were very concerned about his drug use in this town before he died," Pinsky told AAP.

"There were many people who were very concerned."

An autopsy found Ledger, the 28-year-old Australian star of the global box office hit The Dark Knight, died in his Manhattan apartment in January from an accidental overdose of six different drugs, including narcotic painkillers, anti-anxiety pills and sleep medication.

The straight-talking doctor, head of LA's Las Encinas Hospital's department of chemical dependency services and a high-profile figure on American TV, said Ledger was another casualty of a prescription drug abuse epidemic.

"We see this all the time," Pinsky said.

"We have an absolute epidemic of patients dying exactly the way he died - drug addicts."

Asked if he thought Ledger was a drug addict, the doctor replied: "I don't know him, but I've never seen a patient die of that kind of reckless combination of medicine that wasn't a drug addict."

Pinsky has become a household name in the US as star and producer of the US reality TV series, Celebrity Rehab with Dr Drew, and the host of a long-running American radio and TV advice show.

The Celebrity Rehab TV series makes its Australian debut on Foxtel's Bio channel on August 4.

Pinsky, who also works with major US sports leagues, said one-time AFL golden boy Cousins needed to quit football and other activities until he beats his substance abuse problem.

Cousins appears to be planning a football comeback via the second-tier Victorian Football League (VFL), after registering with VFL club Port Melbourne last month.

Cousins has also been offered a spot on the Australian reality TV show, Dancing with the Stars.

Pinsky said playing Aussie rules, no matter at what level, would not help Cousins' recovery if he is yet to beat substance abuse.

"No, that doesn't help," said Pinsky, when told of Cousins' possible move to the VFL.

"They need to stop their life and focus on the treatment.

"They need a structured environment, leave everything, stop their life and take treatment just as if they were taking treatment for cancer."

Pinsky often compares drug abuse to cancer.

Cousins, a former Brownlow medallist and West Coast Eagles star, sparked international media attention last October when he was hospitalised in Los Angeles.

LA's Hermosa Beach police said "a rescue call" was made by one of Cousins' friends who said the footballer "had overdosed on cocaine and had been on cocaine for the prior five days".

Pinsky said of Cousins: "His prognosis is worse than about 80 or 90 per cent of cancers in terms of dying of his addiction."

It was essential that sports teams support players battling addictions, just as they would if the player had cancer, instead of tearing up their contracts, the doctor explained.

"I've done a lot of work with professional sports," Pinsky said.

"Slowly the US professional sports teams have come around to reality, particularly the NBA (National Basketball Association).

"They do a great job. They treat their players.

"They treat them like they have an illness and they give them the medical care and the time."

Pinsky was also disturbed to hear Cousins flew from Perth to Los Angeles for last year's stint at the $US3,000 a day Summit Centre rehab clinic, in the hills above Malibu.

He said he had never heard of the Summit Centre and when told of the cost to stay there, replied: "That doesn't mean shit.

"Listen, these people need to go to a hospital," Pinsky said.

"He has a medical illness.

"He needs to go to a psychiatric hospital so we can treat him.

"That is pathetic that he has to come from Australia (to Malibu)."

The first series of Celebrity Rehab with Dr Drew follows the treatment of a group including actor Daniel Baldwin, porn star Mary Carey, frontman of the rap/metal band Crazy Town, Seth Binzer, Sylvester Stallone's ex Brigette Nielsen, Grease star Jeff Conaway and female professional wrestler Chyna.