What is dexamethasone, the newest drug in Trump’s COVID-19 treatment?

The president’s physician says President Trump was treated with a steroid after a drop in oxygen levels on Saturday.

Dr. Sean Conley said at a news conference on Sunday that he was given the steroid dexamethasone while he was hospitalized at Walter Reed National Military Medical Center.

Conley said the president’s oxygen level had dropped down to 93% on Saturday. He says the president did not feel short of breath.

Trump’s blood oxygen level currently stands at 98%, Trump’s medical team said.

Blood oxygen saturation is a key health marker for coronavirus patients. A normal reading is between 95 and 100. A drop below 90 is concerning.

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Dr. Brian Garibaldi, a specialist in pulmonary critical care, said Trump received a second dose of the experimental drug remdesivir along with a first dose of dexamethasone Saturday and isn’t showing any side effects “that we can tell.”

“In response to transient low oxygen levels … we did initiate dexamethasone therapy, and he received his first dose of that yesterday,” said Garibaldi during a press briefing outside the facility. “Our plan is to continue that for the time being.”

Dexamethasone and similar steroids now are known to improve survival when used in hospitalized patients who need extra oxygen, but might be harmful for less sick patients.

The World Health Organization says dexamethasone is not recommended for non-severe cases; the National Institutes of Health guidelines only recommend dexamethasone for patients with COVID-19 who are on a ventilator or are receiving supplemental oxygen.

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The National Institutes of Health COVID-19 treatment guidelines recommend against using dexamethasone in patients who do not require oxygen. It has only been proven to help in more serious cases. Among the concerns with earlier use is that steroids tamp down certain immune cells, hindering the body’s own ability to fight off infection.

Trump is 74 years old and clinically obese, putting him at higher risk of serious complications.

Trump’s treatment with the steroid dexamethasone is in addition to the single dose he was given Friday of an experimental drug from Regeneron Pharmaceuticals Inc. that supplies antibodies to help the immune system fight the virus. Trump on Friday also began a five-day course of remdesivir, a Gilead Sciences drug currently used for moderately and severely ill patients. The drugs work in different ways — the antibodies help the immune system rid the body of virus, and remdesivir curbs the virus’ ability to multiply.

More than 209,000 Americans have been killed by the virus, by far the highest number of confirmed fatalities in the word. In all, nearly 7.4 million people have been infected in the United States, and few have access to the kind of around-the-clock attention and experimental treatments as Trump.

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