Hydroxychloroquine may not prevent coronavirus infections, and there are risks to taking the drug every day

• President Trump announced Monday that he's taking hydroxychloroquine every day in case it could help prevent a coronavirus infection.
• There's no real evidence yet that hydroxychloroquine, which has been used for decades to treat arthritis, and prevent and treat malaria infections, might prevent people from catching the coronavirus.
• It can have dangerous side effects, including irregular heartbeats and death.
• Trump's doctor said in a letter that he decided "the potential benefit from treatment outweighed the relative risks" for the president.

President Trump has started taking "a pill every day" in the hopes it might prevent him from catching the coronavirus.

"I'm taking it, hydroxychloroquine," Trump told reporters at the White House on Monday. "I'm not going to get hurt by it. It's been around for 40 years for malaria, for lupus, for other things. I take it. Frontline workers take it. A lot of doctors take it."

Trump is, roughly speaking, right about all of that.

Hydroxychloroquine was first approved by the US Food and Drug Administration in April 1955, and has been used for decades since to treat rheumatoid arthritis, lupus, and for both the prevention and treatment of malaria.

It's still not clear whether the anti-inflammatory drug will prevent people from getting the coronavirus, but scientists are looking into the idea seriously, with trials of tens of thousands of healthcare workers underway in countries around the world, including in Spain, the US, Canada, and the UK.

For now, the FDA says the general public should not take hydroxychloroquine to treat or prevent COVID-19, the disease caused by the coronavirus, outside of hospital settings or clinical trials. This is because the drug can interact poorly with other medications, including the common antibiotic azithromycin. It should also not be taken by people with psoriasis.

Serious complications include triggering of irregular heart rhythms, and, in some cases, death. The US Centers for Disease Control and Prevention also cautions that people who take "higher doses" of the drug for "many years" can develop eye damage, and anyone who stays on it for more than five years "should get regular eye exams."

The President's doctor, Sean Conley, said in a letter on Monday that "the potential benefit from treatment outweighed the relative risks" for the president, but said he'll continue to monitor the studies coming out about whether the drug does anything much to prevent COVID-19.

It may turn out that the drug performs just as poorly at preventing COVID-19 as it has at treating the disease, but it's too soon to tell. However, patients who rely on the drug to treat chronic conditions like arthritis and lupus are already dealing with worrisome shortages, as the president doubles down on his praise of hydroxychloroquine and people and clinics around the country continue stocking up.

Vice President Mike Pence, whose staffer tested positive for the virus earlier this month, told Fox News on Tuesday that he is not taking the drug as a COVID-19 prophylaxis, unlike the president.

"It seems to have an impact. And maybe it does; maybe it doesn't," Trump said during his Monday comments. "All I can tell you is, so far, I seem to be okay."