The drug US President Donald Trump has said he is taking to prevent contracting the novel coronavirus has a much higher risk of death among COVID-19 patients, according to a study published Friday. 

The study published in the Lancet peer-reviewed journal looked at over 96,000 virus patients, also found a higher risk of abnormal heartbeats, or arrhythmias, that could cause a heart attack in those treated with hydroxychloroquine or chloroquine.

The study looked at patient medical records in 671 hospitals across six continents, making it the largest published evaluation of the drug's impacts on coronavirus patients to date.

It determined that not only was there "an absence of benefit" from treatments using the drugs, it said they "could even be harmful" to the patients whom receive it as a treatment.

It looked at patients who were administered the drugs either alone or in combination with a type of antibiotic known as a macrolide within 48 hours of their COVID-19 diagnosis.

Those patients who received the drugs had a death rate roughly twice as high as those who did not receive the drugs, with the rate significantly higher for those that also received the macrolide in addition to hydroxychloroquine or chloroquine.

Those treated with hydroxychloroquine, or it in combination with the antibiotic, had a slightly higher mortality rate than those treated with chloroquine.

The drugs are approved to prevent and treat malaria, and hydroxycloroquine has been approved to treat auto-immune diseases.