WASHINGTON (AP) — President Donald Trump and his administration kept up their out-sized promotion Monday of an malaria drug not yet officially approved for fighting the new coronavirus, even though scientists say more testing is needed before it’s proven safe and effective against COVID-19.

Trump trade adviser Peter Navarro championed hydroxychloroquine in television interviews a day after the president publicly put his faith in the medication to lessen the toll of the coronavirus pandemic.

“What do I know, I’m not a doctor,” Trump said Sunday. “But I have common sense.”

Trump held out promise for the drug as he grasps for ways to sound hopeful in the face of a mounting death toll and with the worst weeks yet to come for the U.S. The virus has killed more than 10,000 in the U.S., and measures meant to contain its spread have taken a painful economic toll and all but frozen life in large swaths of the country.

But medical officials warn that it’s dangerous to be hawking unproven remedies, and even Trump’s own experts have cautioned against it.

The American Medical Association’s president, Dr. Patrice Harris, said she personally would not prescribe the drug for a coronavirus patient, saying the risks of severe side-effects were “great and too significant to downplay” without large studies showing the drug is safe and effective.

Harris pointed to the drug’s high risk of causing heart rhythm problems.

“People have their health to lose,” she said. “Your heart could stop.”

In a heated Situation Room meeting of the White House’s coronavirus task force on Saturday, Navarro challenged the top U.S. infectious disease expert, Dr. Anthony Fauci, over his concerns about recommending the drug based only on unscientific anecdotal evidence.

Navarro, who has no formal medical training, erupted at Fauci, raising his voice and claiming the reports of studies he had collected were enough to recommend the drug widely, according to a person familiar with the exchange who spoke on the condition of anonymity to describe the blow-up.

Fauci has repeatedly said current studies provide only anecdotal findings that the drug works. In response, Navarro told CNN on Monday: “I would have two words for you: ‘second opinion.'”

Hydroxychloroquine is officially approved for treating malaria, rheumatoid arthritis and lupus, not COVID-19. Small, preliminary studies have suggested it might help prevent the new coronavirus from entering cells and possibly help patients clear the virus sooner. But those have shown mixed results.

Doctors are already prescribing the malaria drug to patients with COVID-19, a practice known as off-label prescribing. Research studies are now beginning to test if the drugs truly help COVID-19 patients, and the Food and Drug Administration has allowed the medication into the national stockpile as an option for doctors to consider for patients who cannot get into one of the studies.

But the drug has major potential side effects, especially for the heart, and Fauci has said more testing is needed before it’s clear that the drug works against the virus and is safe for use.

Navarro told Fox News Channel’s “Fox & Friends” that doctors in New York hospitals are already distributing the drug to COVID-19 patients and that health care workers are taking it in hopes of being protected from infection. Though he acknowledged the debate with Fauci, Navarro said the focus was on whether the administration should send 29 million doses of the drug in Federal Emergency Management Agency warehouses to hard-hit cities.

“The media is trying to blow it up as a big big debate, but I can tell you that within the room the decision was a sound one, and it was unanimous,” Navarro said.

Asked about his credentials for pushing the drug, Navarro cited his doctorate in social science and said that “in the fog of war, we might take more risks than we otherwise would.” “I’d bet on President Trump’s intuition on this one,” he added.

Administration officials say Trump’s embrace of the drug stems from his desire to provide “hope” for the American people as the death toll mounts and he looks to avoid political consequences from the outbreak.

Some limited studies have been conducted on the use of hydroxychloroquine and antibiotic azithromycin in concert to treat COVID-19, but they have not included critical control groups that scientists use to validate the conclusions.