Immigration Minister Scott Morrison has rejected claims that an Iranian asylum seeker, who has now died in hospital after being transferred to Brisbane from Manus Island detention centre, was not given proper medical care.

Hamid Kehazaei, 24, cut his foot three weeks ago and developed septicaemia before being moved to the mainland for treatment.

He had a heart attack before being declared brain dead on Tuesday. Late Friday his family gave permission for doctors at Brisbane's Mater Hospital to switch off his life support.

Mr Kehazaei died on Friday evening.

A family friend, Tina, has told the ABC's PM program that while Australian authorities have been in regular contact with the family, it remained unclear what had happened to Mr Kehazaei on Manus Island.

"No-one tells the family or the media or anyone what has happened on Manus Island," she said.

"Is there an investigation going on? Is there an update on what has happened with what's the situation that has led to this? No one knows."

Earlier on Friday, Mr Morrison said many accusations regarding Mr Kehazaei had "not been based on any primary knowledge of this case".

"Our focus and care has been on this young man from the moment he presented to medical officers at Manus Island and on focussing on the interests and engaging with the family," he said.

The minister also said he had asked his department's chief medical officer to review the case.

"I would base my assessment of that treatment on the facts, not Facebook," he said.

"I think it's very unfortunate that some advocates and the Greens and others have sought to seek to use this event to make political points."

Activist says medical care wasn't good enough

Refugee Action Coalition spokesman Ian Rintoul accused authorities of taking too long to act.

Mr Rintoul said Mr Kehazaei sought medical attention for days before being flown to Port Moresby, then was put into intensive care at the Mater Hospital last week.

He said Mr Kehazaei was a victim of "the shocking conditions and medical neglect on Manus Island".

"It is inexcusable that he developed septicaemia on Manus Island," he said.

"Nothing else to describe it, but it is just sheer negligence."

The Greens have also called for an urgent investigation into medical care on Manus Island.

In a written statement, Labor's immigration spokesman Richard Marles said the Government had taken the right step in asking the chief medical officer to review the case.

"Mr Morrison needs to ensure that review is made public as soon as possible," he said.

"Labor has strong concerns about the lack of transparency surrounding the treatment of asylum seekers under the Abbott Government.

"Every single Australian-funded facility must be run in a manner that is safe, humane, dignified and allows for proper oversight."

Tina said Mr Kehazaei's family had been told his body would be repatriated to Iran.

"The family was really willing to make something good out of this whole tragedy, so they were thinking about donating any of the organs that is still healthy and can be donated, basically," she said.