The research could mean that a corticosteroid becomes part of the management protocol for acute respiratory distress associated with Covid-19, Dr Christopher Gale said.
There would be 20 per cent fewer deaths from Covid-19 if steroids were part of standard care for critically ill patients, according to a new study.
Recently published research pooled data from seven studies and more than 1700 patients from around the world, including New Zealand, and found fewer patients died and less needed intensive care support when they received steroids compared with usual treatment.
The trials looked at hydrocortisone, and two steroids which are similar to prednisone but more potent - methylprednisolone and dexamethasone.
Each of the steroids had a similar effect on survival rates, which New Zealand author, Dr Colin McArthur, said will help with drug shortages as the pandemic marches on.
McArthur, an Auckland City Hospital ICU specialist, said many hospitals have started using dexamethasone as a treatment in recent months following the results of a UK-based study which found it improved survival rates in patients who had been intubated.
"What we've added here is that hydrocortisone is equally beneficial, and we've confirmed in several other studies that any form of steroid treatment has a similar beneficial effect."
The ability to swap out one steroid for another - and know it will work - is a huge step forward, he said.
"Over the global epidemic there are going to be drug supply issues potentially. Some drugs may be more available or less available in different countries.
"And we know now that we have two viable alternatives which means accessibility has improved."
McArthur said the results should be applied globally.
"It's a very important result. The treatment is not extensive and should be applicable in every health setting in the world, with the benefits of significantly reduced mortality."
He said other treatments still need to be examined to improve survival rates from severe cases of Covid-19.
Consultant psychiatrist and senior lecturer at the University of Otago, Dr Christopher Gale, said it was important to remember that the patients in this trial group were extremely sick.
"Corticosteroids make a small difference, but in people with respiratory distress small differences matter.
"This paper will be read with interest by intensive care physicians and general physicians, and it could mean that a corticosteroid becomes part of the management protocol for acute respiratory distress associated with Covid-19."
Dr Greg Kyle, a professor of pharmacy and at Queensland University of Technology said these steroids work by dampening down the immune system response to Covid-19.
"In some people with Covid, the immune system generates a hyper-response, for reasons that are not clearly understood. This severe reaction results in the body attacking itself and generating severe symptoms and death.
"The steroids calm this reaction down - just like pruning a hedge. We don't want to kill the hedge - that is, completely stop the immune system - we want to trim it back so it is not running rampant, but rather is controlled and still able to function."
As steroids are immune-suppressants, they can't be used to prevent Covid-19, he said, and treating a healthy person with steroids could make them more susceptible to the virus.