"There is no evidence of benefit and there is evidence of harm", Dr. Rob Davidson, an emergency care physician and executive director of the Committee to Protect Medicare, said after the president claimed he's taking the drug.
For those given hydroxychloroquine, there was a 34 percent increase in risk of mortality and a 137 percent increased risk of a serious heart arrhythmias.
Stephen Evans, professor of pharmacoepidemiology at the London School of Hygiene and Tropical Medicine, said more research was needed, but added: "A definitive answer still awaits the results of the randomised trials, but it is clear that the drugs should not be given for treatment of Covid-19 other than in the context of a randomised trial".
Hydroxychloroquine is approved to treat malaria - replacing chloroquine in many parts of the world after the malaria parasite became resistant to chloroquine - as well as some autoimmune disorders like rheumatoid arthritis and lupus, because of its ability to tamp down inflammation.
The woman, who asked to only be referred to as Kim, said she had felt safer knowing that the anti-malaria drug, which she has taken for 19 years to help with her lupus, was gaining global attention as a possible treatment for warding off COVID-19, news station WISH reported.
The US Food and Drug Administration has said hydroxychloroquine should only be used for hospitalised Covid-19 patients or those in clinical trials.
The researchers found that the mortality rate was the highest among those 6,221 patients who received hydroxychloroquine with a macrolide (23.8%), while the treatment of coronavirus with hydroxychloroquine alone in a group comprising 3,016 patients resulted in an 18% death rate.
'The best way to find out if they are effective in preventing Covid-19 is in a randomised clinical trial'.
Frontline health workers in the United Kingdom working for the National Health Service (NHS) will be given hydroxychloroquine, a malaria drug, to assess whether it can prevent COVID-19.
The analysis included data from 671 hospitals across six continents, which pooled together resulted in 96,032 patients who had tested positive for COVID-19 and were hospitalized between December 2019 and April 2020.
All of the patients included in the study had either been discharged or had died by 21 April 2020, the scientists said.
There was also a control group of patients not given these treatments. "Based upon these findings and others, no one should take hydroxychloroquine with or without an antibiotic unless they are in a randomized controlled trial".
- A 37% increase in risk of death for those given chloroquine, and a 256% increase in risk of serious heart arrhythmias.
At a press conference earlier this week, US President Donald Trump said he was taking hydroxychloroquine as a "preventative" measure.
The study accounted for several "confounding factors", like, age, sex, race or ethnicity, body-mass index.
However, they said it is not possible to exclude the possibility of unmeasured factors being responsible for the link.
The study backs up earlier reports of scant or no evidence the drugs were useful in treating coronavirus.
Notably, studies have been inconclusive over the drug's efficacy against the disease and some even suggest it may worsen a patient's condition.
"Whilst not a placebo controlled trial, an observational study on this scale undertaken with stringent and meticulous analysis is powerful indeed".