When patients ask, what should clinicians advise about hydroxychloroquine to treat coronavirus?

Patients who a short time ago had never heard of two antimalarial drugs might now be asking clinicians about them as a treatment for COVID-19.

So what should clinicians advise about the use of the drugs—hydroxychloroquine and chloroquine—to treat coronavirus?

Doctors and other clinicians should avoid misuse of the drugs “for the prophylaxis of COVID-19, because there are absolutely no data to support this,” according to two doctors, writing in an “ideas and opinions” piece in the Annals of Internal Medicine.

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The two generic drugs, used largely by rheumatologists and dermatologists to treat immune-mediated diseases, such as lupus and rheumatoid arthritis, entered the spotlight after President Donald Trump suggested hydroxychloroquine could be a potential treatment for COVID-19.

That accelerated a worldwide run on the drugs, with pharmacies reporting shortages within 24 hours, said Jinoos Yazdany, M.D., of the Zuckerberg San Francisco General Hospital and the division of rheumatology at the University of California, San Francisco, and Alfred H.J. Kim, M.D., of the division of rheumatology at Washington University School of Medicine in St. Louis.

Both drugs have demonstrated antiviral activity against severe acute respiratory syndrome–coronavirus 2 (SARS–CoV-2) in vitro and in small, poorly controlled or uncontrolled clinical studies, research that would normally be deemed hypothesis-generating at best, the two rheumatologists said.

Data to support the use of either drug for COVID-19 are “limited and inconclusive,” they said. Sadly, reports of adverse events have increased, with several countries reporting poisonings and at least one death reported in a patient who drank fish tank cleaner because it contains chloroquine. The drugs can have side effects including ventricular arrhythmias, chloroquine prolongation and other cardiac toxicity, which may pose a particular risk to critically ill persons.

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“Given these serious potential adverse effects, the hasty and inappropriate interpretation of the literature by public leaders has potential to do serious harm,” they wrote.

Instead of treating patients with coronavirus with the drugs, physicians should refer patients to expedited randomized trials that can answer the question of if, when, and for whom the medications are helpful in COVID-19, they said. Ten such trials are underway.

That leaves the question of how to help patients with immune-mediated conditions that do benefit from the drugs that are now in short supply.

The doctors said landmark clinical trials have shown that the withdrawal of hydroxychloroquine from patients with lupus can lead to flares of the disease, including life-threatening effects.

“The current shortages of HCQ [hydroxychloroquine] have therefore alarmed rheumatologists and patients. Offices across the country report fielding calls from concerned patients who are having difficulty obtaining their medication,” they wrote.

Studies have shown that brief gaps in therapy, of about one to weeks, are less concerning, but longer lapses put patients at risk, they said. Patients may wonder about rationing their supply of the drug by taking a lower dose, which isn’t a good idea, although it may be that some patients do better than others with that approach, they said.

Given the likelihood that shortages will continue, the doctors called on manufacturers, clinicians, pharmacies, health systems and governmental health agencies to take an aggressive response to ensure use of the drugs is managed during the pandemic.

Finally, they said health professionals must stop depleting the supply by prescribing the drugs and hoarding them for themselves, family and friends.

“The looming public health crisis for people with rheumatic diseases who will be unable to obtain HCQ is the result of a perfect storm of fear and dissemination of overpromised data,” they said.