A large study, published by the Lancet medical journal, indicated that malaria, hydroxy chloroquine, which US President Donald Trump says he is taking and urging others to use is linked to an increased risk of death for Covid-19 patients whose condition requires treatment in Hospitals.
In the study, which examined more than 96,000 new cases of coronavirus in hospitals, it was found that those treated with hydroxychloroquine, or chloroquine, were more likely to die than patients who were not treated with the two drugs.
The authors of the study said they could not confirm whether taking this drug offered any benefit to patients with "corona".
They wrote, "There is a need for rapid confirmation from randomized clinical trials." The study did not include drug-controlled trials, compared to placebo.
Injuries to patients treated in hospital are usually more severe than others. Some advocates of using the two drugs as a treatment for the disease say that they may need to be used at an early stage to be effective.
The demand for hydroxychloroquine, a decades-old treatment, has increased with Trump's repeated pressure to use it to treat the virus, and his demand for people to try it. He said: "You will not lose anything."
Trump said this week that he was using hydroxychloroquine as a preventative treatment, despite the lack of scientific evidence.
The authors of the study, published in the Lancet, suggested that the two drugs are not used as a treatment for disease other than clinical trials, until studies confirm their safety for Covid-19 patients.
The US Food and Drug Administration said that hydroxychloroquine should only be used with Corona patients in hospitals or in clinical trials. The two drugs were linked to serious heart rhythm problems.
The study looked at data from 671 hospitals, where 14,888 patients were given, either hydroxychloroquine or chloroquine, with or without an antibiotic, and 81,144 patients were not treated with these drugs.