Trump was treated with dexamethasone. Here’s what we know about its risks and side effects.

President Donald Trump’s team of physicians revealed Sunday that he was being treated with dexamethasone, and health experts immediately voiced concern. The powerful steroid has shown promise for treating severe COVID-19 patients, but may cause harm for those with minor infections.

The use of dexamethasone, experts say, contrasts with White House physician Sean Conley’s rosy assessments of Trump’s battle with the virus. Typically used to treat inflammation, dexamethasone was credited with improving the survival for critically ill coronavirus patients in a study published in the New England Journal of Medicine.

Trump’s doctors at Walter Reed National Military Medical Center cited the positive research when they disclosed that they prescribed the steroid after Trump’s oxygen levels concerningly dropped to 93%.

For COVID-19 patients on ventilators or receiving oxygen, taking dexamethasone increased their chance of survival, according to the research published in July. But dexamethasone-receiving patients who didn’t require ventilation or oxygen fared no better than patients on the normal course of treatment.

In fact, giving dexamethasone to coronavirus patients who are not at risk of severe illness could further endanger their health, according to an August paper in the Journal of Hospital Medicine.

In its guidelines, the National Institutes of Health recommends against using dexamethasone for COVID-19 patients who do not require supplemental oxygen.

Dexamethasone is not often prescribed toward the start of a patient’s infection, experts say, because it can suppress the immune system’s ability to ward off the virus. But Trump’s doctors opted to prescribe the steroid less than two days after Trump publicly disclosed that he tested positive.

“We decided that in this case the potential benefits early on in the course probably outweighed the risks,” Conley said Sunday.

Dexamethasone can also have concerning side effects, ranging from blood clots, blurred vision, and headaches to “psychic derangements,” such as insomnia, mood swings and “frank psychotic manifestations,” according to the drug label.

Doctors know what to expect with dexamethasone because the drug itself is nothing new. Used to treat asthma, Crohn’s disease, IBS and some cancers, the steroid is 60 years old and ubiquitous.

“It’s cheap as borscht, as my grandparents would say,” Isaac Bogoch, an infectious diseases specialist at Toronto General Hospital, previously told The Washington Post. “It’s widely available. Every single physician on the planet that practices hospital-based medicine is comfortable using this drug.”

Another well-known, therapeutic effect of the drug is a sensation of euphoria. But the relief a patient may feel should not be confused with physical improvement, said Paul Bach, the director of the Center for Health Policy and Outcomes at Memorial Sloan Kettering Cancer Center.

Before departing Walter Reed, Trump boasted on Twitter Monday that he felt better than he did two decades ago.

“Feeling really good! Don’t be afraid of Covid. Don’t let it dominate your life,” Trump wrote after his brief hospitalization for the virus that has killed more than 210,000 Americans.

Patients who are prescribed a steroid like dexamethasone can over-exaggerate how well they feel, Bach told The Post. But he advises patients who take the steroid not be deceived by the reprieve and overexert themselves.

“Having taken this myself, for a herniated disc, I felt like a million bucks,” Bach said, “but actually I was barely able to move.”

Trump was prescribed the drug in concert with other medicines - supplemental oxygen, a monoclonal antibody cocktail and a five-day course of the intravenous anti-viral remdesivir.

It’s not fully known how dexamethasone interacts with the two experimental therapeutics - or even how Trump has responded.

The president’s condition, including when he first tested positive, has been shrouded in secrecy. His doctors have dodged questions from reporters, which has complicated efforts for physicians and experts on the outside to weight in about his care, including how effective dexamethasone is.

Céline Gounder, an infectious-disease professor at New York University and Bellevue Hospital Center, said she was unable to assess if dexamethasone was the best course of treatment for Trump given how little is known about his bout with the disease.

Dexamethasone is recommended administered a week into illness for severe COVID-19 patients, but that depends on the lab results of the patient, which in Trump’s case, have not been shared publicly.

“If they would release full details, it would be much easier to say ‘OK, this makes sense’ or not,” Gounder said.

Given what is known about dexamethasone, Gounder warned that the steroid could obscure the symptoms of the disease caused by the virus. For instance, the steroid can suppress a fever.

“Treating with dexamethasone can confound the picture,” Gounder said.