Malaria experts are changing their advice after a study showed a drug can save more lives than current therapy.
Mosquitoes carry the malaria parasite
The World Health Organization said it will recommend artesunate, a drug derived from traditional Chinese medicine, for severe malaria.
The move follows a Lancet study that showed using this drug in adults living in areas of low malaria transmission cut deaths by over a third.
Previously, doctors often used quinine based drugs to treat severe malaria.
The trial, funded by the Wellcome Trust and conducted in Bangladesh, Burma, India and Indonesia, compared the effectiveness of quinine and artesunate.
The death rate was much lower among the adults who received artesunate compared to those who received quinine - 15% compared with 22%, respectively.
Lead researcher Professor Nick White, who is chairman of the Wellcome Trust South East Asian Tropical Medicine Research Programmes and an expert adviser to WHO, said: "The difference in mortality is huge. For between every 11 and 20 patients who come into hospital you save one life.
"Until this, there has never been any trial in severe malaria which showed a clear difference in mortality between the two treatments."
He said artesunate should now be the first treatment of choice rather than one of the treatments of choice for severe malaria.
Professor White said a trial was currently being conducted to see if the same is true in children with severe malaria.
He said artesunate was also easier to use and slightly cheaper than quinine.
Dr Peter Olumese from WHO and Roll Back Malaria said: "For the first time they have shown a mortality advantage of artesunate over quinine.
"Now we can make recommendations that in areas of low disease transmission, artesunate would be a preferred option over quinine for adults with severe malaria."
He said new guidelines advising doctors of this would be published soon.
Dr Olumese and Professor White said the issue now was to make sure that the drug was available to those who need it.
Professor White said artesunate was not yet approved by regulatory authorities in many countries, which was a problem.
Dr Olumese added: "Unless something is done to increase production, supply might become an issue."
There are some 300-500 million cases of malaria each year, with one million resulting in death.
About 80% of the deaths occur in areas of high transmission and the remaining 20% in areas of low transmission, said Dr Olumese.