President Trump's raising of unproven, even far-fetched ideas for fighting Covid-19 - including his latest musing about injecting disinfectants into people - triggered an outcry from health officials everywhere.
It also highlighted his unconventional approach to the special responsibility that comes with speaking from the presidential pulpit.
Trump readily admits he's not a doctor. Yet with the reported US death toll from the virus topping 50,000, he continues to use the White House podium to promote untested drugs and float his own ideas for treatment as he tries to project optimism.
"He's like the family member around the dinner table that doesn't have a grasp of what reality is and is willing to speak with confidence despite it," said Julian Zelizer, a presidential historian at Princeton University. He said Trump likes to provocatively push the boundaries because he thinks that appeals to his political supporters.
"But in this case it's the president of the United States and it's dangerous," Zelizer said.
Trump's offhand comment last Thursday wondering if disinfectants could be injected or ingested to fight Covid-19 was met with intense criticism from doctors and other health officials. It also prompted blunt warnings from the makers of popular commercial products.
"We must be clear that under no circumstance should our disinfectant products be administered into the human body (through injection, ingestion or any other route)," said a statement from the company that makes Lysol and Dettol, Reckitt Benckiser.
"Bleach and other disinfectants are not suitable for consumption or injection under any circumstances," declared the Clorox Co.
The White House said the president's comments had been misrepresented by the media, and Trump said he had been speaking sarcastically. But a transcript of his remarks suggested otherwise.
He had noted that research was under way into the effect disinfectants have on the virus and wondered aloud if they could be injected into people.
"Is there a way we can do something like that, by injection inside or almost a cleaning?" Trump asked. "Because you see it gets in the lungs and it does a tremendous number on the lungs. So it would be interesting to check that."
Don't try that at home, others quickly warned.
The US Surgeon General's office tweeted a reminder to all Americans: "PLEASE always talk to your health provider first before administering any treatment/ medication to yourself or a loved one."
Democrats leapt to respond. "I can't believe I have to say this, but please don't drink bleach," tweeted Joe Biden, the Democrats' presumptive presidential nominee.
Speaker of the House Nancy Pelosi accused Trump of suggesting that people "inject Lysol into their lungs".
Speaking to reporters last Friday, Trump insisted his comments were misconstrued. "I was asking the question sarcastically to reporters like you, just to see what would happen," he said.
Dr Deborah Birx, coordinator of the White House coronavirus task force, said Trump was merely thinking aloud about what he was hearing at the briefing.
The White House also has pitched "emerging" research on the benefits of sunlight and humidity in diminishing the threat of the virus. Past studies have not found good evidence that the warmer temperatures and higher humidity of spring and summer will help tamp down the spread of the virus.
Read Declan Lynch, P20