Brazil's president says he is taking hydroxychloroquine to cure his coronavirus. Scientists have long said it doesn't work.

• Brazilian President Jair Bolsonaro, who has tested positive for the coronavirus, said Tuesday that he is taking the contentious antimalarial drug hydroxychloroquine to treat his symptoms.
• The drug is widely considered ineffective as a treatment for COVID-19, and can result in serious side effects.
• The US Food and Drug Administration has not approved the drug, France has banned it, and the WHO dropped it from its COVID-19 treatment program.
• US President Donald Trump — a world leader revered by Bolsonaro — said in May that he was taking the drug as a precaution.

Jair Bolsonaro said on Tuesday that he is taking the contentious antimalarial drug hydroxychloroquine to treat his coronavirus infection.

The Brazilian president tested positive for what he calls the "little flu" on Monday after contracting a cough and fever over the weekend.

Hydroxychloroquine has been banned in France, dropped from the World Health Organization's trial program, labelled dangerous by experts, and has not been approved by the US Food and Drug Administration (FDA).

In mid-March, the FDA briefly greenlit the drug for emergency use in severe coronavirus cases, but that waiver was withdrawn on June 15 following weeks of debate over its safety.

The key problem is that while the drug may work on the coronavirus in the lab, it does not work the same way in the human body, and could trigger serious side effects.

Donald Trump, who revealed on May 18 that he was taking the drug as a precaution, has advanced it as a treatment.

"I took it and I felt good about taking it. I don't know if it had an impact, but it certainly didn't hurt me," he said.

Bolsonaro's infection caps off a terrible period for Brazil, where it has been one of the worst-hit countries in the pandemic.

As of Wednesday, 1.7 million people have tested positive and 66,868 people have died, according to a tracker from the G1 Globo news outlet.

Cases and deaths are still high, but the country is pressing on with ending its lockdown and reopening businesses and venues.

Throughout the pandemic Bolsonaro also repeatedly flouted public-health guidance and downplayed the severity of the outbreak.

He told TV Brasil on Tuesday that his lungs were scanned on Monday after he felt pain, but by Tuesday his fever was better, which he said was thanks to hydroxychloroquine.

Nonetheless, a number of studies have found hydroxychloroquine to be ineffective in treating COVID-19.

"These large observational studies have found no evidence of benefit and perhaps some evidence of harm," Dr. Neil Schluger, chairman of the department of medicine at New York Medical College, previously told Business Insider.

A handful of other studies, however, have indicated that the drug has seen some success in hospitalized patients.

Some 50 million hydro chloroquine pills are currently lying in US government storage, after the Trump administration stockpiled them before the FDA withdrew the waiver.

Hydroxychloroquine is also a key treatment for lupus and rheumatoid arthritis.