The comments came two days after he announced he had taken the anti-malaria drug on a daily basis for some two weeks as a preventative measure against the novel coronavirus, reports Xinhua news agency.
Those who are chronically on hydroxychloroquine for anti-rheumatic purposes or the treatment of lupus are generally more at risk, and should undergo comprehensive eye exams more often.
"You have to have a discussion with your doctor to decide if it is best for you", Dr. Janette Nesheiwat, a Fox News medical contributor, warned.
The mainstream liberal media attacks President Trump no matter what he says and does, no matter what he doesn't say or do.
Facts First: There are several ongoing studies in the United States to see if hydroxychloroquine successfully prevents frontline medical workers from getting infected by the virus.
Ryan went on to note that warnings have been issued by "many authorities regarding the potential side effects of the drug".
Early studies from China and France seemed to show COVID-19 patients recovering more quickly on the drug, but critics pointed out numerous flaws, including the lack of peer review and the small sample size. More than a thousand subjects in all are being tested with hydroxychloroquine and placebos.
The Duke Clinical Research Institute is leading a study to, in part, determine if hydroxychloroquine can successfully prevent coronavirus infections in health care workers with a high risk of infection.
"Urgent confirmation from randomized clinical trials is needed", they wrote.
World Health Organization warns against using hydroxychloroquine outside clinical trials
"Despite the lack of strong evidence, these drugs are being widely recommended and they are being widely used in some countries - so finding out if they can protect against covid-19 - yes or no - is of tremendous importance".
"The indications are that these drugs certainly ought not to be used outside of a trial setting where patients can be monitored for complications", said Griffin, who was not involved in the study.
"I get a lot of tremendously positive news on the hydroxy, and I say.what do you have to lose?" the president told reporters.
Two large observational studies, each involving around 1,400 patients in NY, however, also recently found no benefit from the drug.
For three months the participants in the UK, Europe and Africa, will be given doses of either hydroxychloroquine or a placebo.
Since then, several studies have tested the use of hydroxychloroquine to treat coronavirus.
At the end of the study period, around one in 11 patients in the control group had died in hospital, they said.
Kim believed she would no longer contract the virus because Trump has been promoting it touted the drug as effective.
CORONAVIRUS: Lyon County Public Health reports 1 new COVID-19 case Featured
Officials said the Bulverde and Canyon Lake cases are those with household contact with previously confirmed cases. The Georgia Department of Public Health is now providing updates at 9 a.m., 1 p.m. and 7 p.m. on their website .