Australian policy-makers must be willing to turn society upside down to flatten the "mental health curve" stemming from COVID-19, an eminent psychiatrist says.

An eminent psychiatrist has warned a second wave of coronavirus-linked mental health cases is crashing down on Australia, with the nation ill-equipped to flatten the curve.

In an editorial published on Monday in the Medical Journal of Australia, Patrick McGorry said the fallout from the COVID-19 pandemic would be felt more keenly by particular at-risk groups.

The former Australian of the Year said a survey from the first month of the coronavirus pandemic confirmed the initial impacts on mental health had been severe.

As COVID-19 cases continue to dwindle, Professor McGorry cited predictions from more recent scientific models that Australia would face a "second curve of mental ill-health and suicide".

"This has now clearly arrived," he wrote.

"The thinking behind how to deal with the unique demands that COVID-19 has placed on our mental health response is outdated; a major effort to increase the capacity of our mental health system is required.

"The capacity of the mental health system, even before COVID-19, had been inadequate for responding to the demand, and the same system is now expected to respond to the surge in need for mental health care."

That surge is likely to be driven by women, unemployed, marginalised, disadvantaged and young Australians, identified as groups at major risk for detrimental health and social outcomes.

Prof McGorry, executive director of peak youth mental health body Orygen, said levels of socio-economic inequality become "blaring" when the pandemic is coupled with a recession.

"We may all be in this together but some are further in than others," he said.

The global financial crisis demonstrated the destructive flow-on effects of austerity policies on mental health, he said, with measures such as JobKeeper and JobSeeker softening the blow in Australia thus far.

Prof McGorry is calling on policy-makers to adopt a unique approach to reform and strengthen the system, including shifting the focus of mental health care from large hospital-centric networks to local communities.

"We have been willing to turn our society upside down to flatten the COVID-19 curve, the same commitment is now required to flatten the mental health curve," he said.