Doctors are treating Donald Trump with a steroid given for serious coronavirus infections after his blood oxygen level dropped twice.
White House physician Dr Sean Conley said the US President was started on dexamethasone, which has been shown in studies to improve survival for patients hospitalised with critical COVID-19 who need extra oxygen.
It follows two concerning drops in his oxygen levels – one episode where it fell below 94 per cent and another where it was below 93 per cent.
Dr Conley is holding out hope Mr Trump could be discharged from hospital as early as Monday (local time), telling reporters the president has been able to walk around.
“The fact of the matter is, he’s doing really well,” he said.
But confusion remains over the exact nature of Mr Trump’s condition.
There have been conflicting reports about his health from doctors who maintain Mr Trump’s condition is improving and the White House chief of staff, Mark Meadows, who has given reporters a less rosy assessment.
“The president’s vitals over the last 24 hours were very concerning and the next 48 hours will be critical in terms of his care,” Mr Meadows said on Saturday.
“We’re still not on a clear path to a full recovery.”
Dr Conley said he was trying to reflect Mr Trump’s “upbeat attitude” when he previously declined to say that the president had been given oxygen.
He confirmed on Monday morning that Mr Trump had to be given supplemental oxygen twice during his stay at Walter Reed National Military Medical Centre.
Doctors said Mr Trump has not run a fever since Friday and that his liver and kidney function remained normal after the second dose in a five-day course of Remdesivir.
The intravenous antiviral drug has been shown to shorten hospital stays.
Asked what tests had revealed about the condition of Mr Trump’s lungs, Dr Conley said there were “some expected findings, but nothing of any major clinical concern”.
Mr Trump is also being given an experimental treatment, Regeneron’s REGN-COV2, as well as zinc, Vitamin D, famotidine, melatonin and aspirin, his doctors have said.
“Today he feels well, he’s been up and around. Our plan for today is to have him eat and drink, be up out of bed as much as possible, to be mobile,” Dr Brian Garibaldi said.
“And if he continues to look and feel as well as he does today our hope is that we can plan for a discharge as early as tomorrow to the White House where he can continue his treatment course.”
Mr Trump released a four-minute video on Sunday in which he said the “real test” of his condition will come over the next few days.
Referring to COVID-19 as “coronavirus or whatever you want to call it”, Mr Trump spoke of the drugs he was prescribed as “miracles coming down from God”.
He said his wife Melania was “doing well”, adding that she was “slightly younger” than him – at age 50, compared to his 74 – and “handling it statistically like it’s supposed to be handled”.