An asylum seeker who once reportedly cut open his stomach during a hunger strike to prove it was empty is at risk of death and must be brought to Australia for treatment, prominent human rights lawyer Julian Burnside QC says.

Mohammad Albederee, a married Iraqi father-of-three who is detained at Papua New Guinea's Manus Island, recently had a fit and "bashed his head against a wall until he lost consciousness," Mr Burnside said.

"He was sent to hospital bleeding from the head, the nose and the ears," he said, adding he understood Mr Albederee can no longer take fluids or solids and struggled to accept intravenous hydration.

The Immigration Department says the man was not close to death and "continues to receive appropriate clinical care in Papua New Guinea, delivered by health professionals as required".

Mr Burnside said he contacted the office of Immigration Minister Peter Dutton and spoke to Labor leader Bill Shorten about the case.

"The department needs to be very quick off the mark. I think he needs to be [evacuated], probably to an Australian hospital, to get proper care," he said, adding his life was "at serious risk".

Asylum seeker advocates had alerted officials to the man's condition and "if he dies, he dies with their knowledge of the risk. The sad truth is whatever happens whether he lives or not, he is likely to be seriously damaged long-term," Mr Burnside said.

The government has previously been reluctant to bring offshore asylum seekers and refugees to Australia for treatment, and Mr Dutton has previously said they should not attempt to seek permanent resettlement in Australia once brought here.

In July, when Mr Albederee had been on a hunger strike for 100 days, Mr Dutton said he had access to world-class health care facilities in PNG.

Asylum seeker advocate Jeanie Walker reportedly told the ABC in October that Mr Albederee "became really distressed so he cut his stomach open to prove there was nothing in it".

Ms Walker told the ABC he "shouldn't still be alive but he's also now struggling with fluids, so he's not going to be around for much longer".

Mr Albederee is believed to have stopped eating after an alleged assault by guards at the detention centre last year.

Asylum seeker advocate Sarah Smith, who is in phone contact with Mr Albederee, said on Monday his wife in Iraq was "very, very worried about him".

She said he had tried to boost the spirits of his fellow detainees, even in his own perilous state.

"Even during these months when he can't feel his legs any more, where he's lapsing in and out of consciousness, he actually sits up all night with his friends keeping them from committing suicide," she said.

Mr Dutton and Mr Shorten have been contacted for comment.

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